I started figure painting about a year ago. As an armor guy /1:35 scale/, figure painting is a completely new challenge to me and I am still learning. I am a hobbyist, a pure amateur.
The first thing I have recognized, how quickly I spent a hell lot of money on different paints, trying to find the right one for my taste.
Without any scientific approach, here are some rather subjective findings about paints and tools I have invested into. I hope this might help optimizing your shopping list as a beginner.

Primers: Painting mainly resin figures, I was looking for something robust. As a beginner, I might pay too much attention to the smoothness of the primed surface, so I keep sanding, fixing casting errors etc until it is perfect. From this perspective the Tamiya Super Fine Surface Primer is the most indestructible primer I have found. Close second is the Gunze Primer Surfacer. Both are Lacquers, adhering well to resin, but not health friendly. As an alternative acrylic primer I find Badger Stynylrez quite good /obviously not as robust as a Lacquer/, and works as a brush on primer as well.
If you are a beginner like me, you might find useful the fact that an acrylic paint can be removed, from a figure, using Vallejo Airbrush Cleaner, which does not attack the above mentioned Tamiya or Gunze primers. You can re-start painting if you wish.

I have been using Gunze/Tamiya acrylics for more than 20 years, but those are for airbrushing /and solvent based acrylics/. I was keen learning more about brush painting with water soluble acrylic.

First lesson- The paint: While manufacturers keep the paint recipe secret, we can certainly say the pigment, binder and the additives defining the paint characteristic. The acrylic polymer/resin is the binder/glue holding the pigments together and adhering to the surface.
The acrylic polymer itself and the composition of additives differ by Manufacturer, resulting in a unique behavior of the paint among others. Glazing as a popular technique, require a very translucent layer of paint, allowing the color below showing trough. For armor guys: it is like a filter with very few pigments. Mixing your own glazes from normal acrylic paint, you basically overthin the paint reducing the number of pigments in the paint film. How opaque the pigment itself is important, but I will skip this part now. Acrylic resin differs by Manufacturer and they tolerate overthinning differently /strictly using distilled water only for thinning/. As soon the acrylic resin not able forming a film , it will release the pigment to the surface. It is called chalking in English, I think. If you are not looking for this particular effect, it is simply ugly. The chalking is prevalent using light colors over dark surfaces /titanium dioxide as pigment is prone to this effect/. I find Schmincke Primacryl /tube version/ having the best resin from this perspective. /comparing to GW, Vallejo, P3, Liquitex Heavy Body, Army Painter/. P3 is also a very good paint, but my local shop stopped selling them.
I would say Vallejo Model range is ok as an acrylic paint /some say it is mixed with vinyl resin, but it is not the case anymore, it is pure acrylic polymer/. For beginners Vallejo still has a huge benefit, because many SBS articles describing the painting process using Vallejo paints.
Scale75 is a unique acrylic paint with a real death matte finish. Although I consider the resin in the Scale75 paint average quality, the pigmentation, the selection of the colors still makes them worthy to buy.
GW paints are real acrylic polymer paints /no vinyl/, just overpriced. So far I could not find any evidence that any of the model paint manufacturers producing anything better than student grade paints /which is till good quality for many of us/, which is quite funny considering that top quality artist paints are cheaper.
From Army Painter I have few colors only, nothing special to mention.
No science here, just a recommendation to grab a tube of Primacryl or P3 and give a try, before investing into the whole range of any brand.
You might also use premixed washes for glazing, or use mediums containing resin for mixing.

Second lesson - The mediums. In short these are the additives /some pre-mixed into the paint already/ changing the drying time, transparency, viscosity, sheen etc of the paint.
This is the same story as with the paints, huge differences among the manufacturers. First note: while artist grade acrylics and mediums represent very good quality, both the paint and many mediums dry with gloss or semi-gloss surface. /exception of Jo Sonja and Vallejo Artis Acrylics, none of them available in my country unfortunately/. Some mediums contain resin/acrylic polymer, some not. Those lacking the resin are pure additives, without any binding power of the resin, therefore there is a limit how much of the medium can be mixed into your paint. Those with resin, can be mixed into the paint as much as you wish /sort of/. Among the mediums, the Matte medium is the one I use heavily. Liquitex Ultra Matte Medium is far the best I used so far /vs Vallejo, Amsterdam, GW Lahmian/. There are 2 main reasons using Matte medium. 1. Reduce gloss of the paint and washes. With artist acrylics it is must have, it is quite useful for model paints as well, because none of them are death matte /except Scale75/. 2. A paint, wash, glazing layer adheres to a matte surface better than to glossy surface. In the worst case nothing binds to the glossy surface. Use matte medium to prevent this. Alternatively you can use matte varnish to overcome gloss surface adherence problems. Tamiya X21 Flat base works to certain extend to reduce gloss, but it is not a real medium, but more a silica powder.
As soon you learn about blending technique, you will hear about retarders. Retarder medium is slowing the drying time of the acrylic paint. Usually Fluid retarder do not contain any binder/glue, so the proportion added to the mix shall be well controlled. Too much retarder might prevent the acrylic polymer forming a film layer, and will never really dry.
Next you might start creating washes, were Flow improver is coming into the picture. As the name suggest it helps with the flow of the paint. This additive helping braking the surface tension of water.
Both retarder and flow improver required during airbrushing acrylics, with a product like Liquitex Airbrush Medium you might get what you need for both blending and mixing washes.
Two more point to be considered when using additives. In general they reduce the strength of the acryl film layer, use sparingly /except those containing resin/. You might re-consider licking your brush during painting, especially when using Flow improver. Read the label, some ingredient might be nasty.

Third lesson - water palette. Might be the most important lesson for a beginner. There are many articles about it, you can easily create your own wet palette. As a sponge any water absorbent kitchen type is fine, as long it is white /Vileda has some/. As a beginner introducing color shifting into your mixing process, due to the color sponge below your wet paper, is just too big challenge. The usual recommendation for the paper is to go with baking/parchment paper. Depending on your country, it might be the way to go, but I have no success with the baking papers from my country. Main issue is they dissolve quickly after adding water and introducing fiber parts into the paint mix. I bought Mr Black wet palette, which has a sheet of both Masterson and Rowney special paper /the 2 main supplier of wet palette for artist shops/. I use Masterson because it is thicker.

And the most important tool – the brush. The usual recommendation is Winsor Series 7. Easy one, so I went to the only local shop selling these. No luck. Spending half hour examining Series 7 0/1/2 size brushes I was not impressed. The sharpness of the tip, density and the form of bristles differed on each one of them. Calling the local distributor I figured that it might be just a bad batch, or since they are made in China QC dropped. No idea.
I ended up buying brushes from a local shop, who is rebranding smaller German/ Japanese/ Chinese manufacturers products. I have also learned from them, that there are still many small brush manufacturers, so it is worth asking around in your country.

Summarizing all this, the recommended shopping list for a beginner
- Mr Black wet palette / or a DIY
- Badger Stynylrez primer /or re-packed version from Ultimate, MIG etc
- Vallejo Model Color Face/Skin 16 set /widely available and reasonable price
- 60ml Schmincke Primacryl Titanium White /because of the resin quality and this is a real opaque white
- Liquitex Ultra matte medium or Liqiutex Matte Medium
- Liquitex Airbrush medium /as retarder and flow improver/

Even if you are not a born Michelangelo/I am definitely not/, with practice you might get some pleasing results. Choosing the right tools from the beginning, helps a lot preserving your motivation.

There are many brands missing, due to the lack of availability in my country, like Golden, Jo Sonja, Winsor Artist, Atelier Interactive, Vallejo Artist etc. Sonner or later ...

Most of your info is spot on, well researched.
Vallejo doesn't have any vinyl in it. At least, not anymore. Older bottles had vinyl on the label, but newer ones do not. When I talked to Alex Vallejo at the 2015 AMPS International, he said that Vallejo paint is 100% acrylic polymer.

Part 2
There are many excellent articles about painting techniques, color mixing, painting with brush on the internet. I am nowhere near describing them any better. As a technical person I have tried structuring the overwhelming number of various techniques a bit differently. This is the summary
Perception of the colors
When we start painting we are putting pigments onto the surface of our miniatures. Actually, there is no color of the pigment, but the reflection of certain spectrum of the visible daylight. We have the sun as the light source, providing the whole visible spectrum /all colors together creating white/. Technically, during painting we manipulate our pigments absorbing light, and allowing only the desired color to be reflected. Mixing the primary colors together /Red, Yellow, Blue/ will give as variant of black , absorbing all the colors. Luckily, in the presence of light, all black paints reflect some light, so we can perceive various shades of black. /Fyi this is Subtractive color model/
See /Pic 1/
Manipulating layers and transparency
There is something else to be considered in our light manipulation. The opacity or hiding power of the paint/pigment. Titanium white is an opaque paint, hiding the color of the layer below. Zinc oxide is a translucent pigment, allowing the light passing through and bouncing back from the blue layer below. With transparent layer we have created our first visual effect, without mixing any color, and added new tint of blue to our composition. /See pic 2/
In the above case we assumed that both whites having the same thickness, and the same volume/proportion of pigment in the layer we have applied. The only difference was the pigment covering/hiding power.

It is important to note that during layering, at least the below paint layer is dried and there is no mixing/ interchange of pigments happening between layers. We utilize the transparency only, creating any visual effect.

We can also manipulate the transparency of the applied layer with the volume of pigment. More pigment will decrease the amount of light passing through We can achieve this with thicker layer /not the initial way to go painting rather small minis/, or applying more thin transparent layers.
/See Pic 3/. 2nd white layer reflect 50% of the light, 3rd layer 75%, 4th layer 100%. So the transmitted amount of light reaching the blue layer below reducing layer by layer.

This was the part explaining how transparent layers /glazes, washes, filters/ work.

Assuming that pigment is the only reflecting material in our layer, controlling the load, and distribution of the pigment in the layer, will bring us even further in controlling the transparency, and the visual effect. When you load your brush with paint, and move on the surface of the mini, you unload the paint to the surface. As long the paint layer is still wet, we can move the pigments around by pushing or pulling them into a certain direction. Yes, the funny zig-zag moves in many tutorials. I am not demonstrating these blending, feathering techniques just highlighting what is the desired result in the structure of the layers. Privateer Press has excellent video tutorials about these techniques. /See pic 4/

So far we have not considered the most obvious way controlling the pigment load in our layer. Water soluble acrylic paints can be diluted with water /distilled water preferably/. Depending on the polymer resin of the paint , they all tolerate thinning with water up to a certain level. As soon you recognize that your diluted glaze/ wash/filter is not binding to the surface, it is mainly the resin losing his gluing power and pigments are not kept together. Luckily mediums /like the above mentioned Liquitex Matte Mediums/ will help overcome this problem. Other benefit using artist grade mediums, that depending on the paint brand you use, they might have better quality resin than the paint itself.

Please consider that regardless how much you thin an opaque pigment, you might never get to the desired transparency. Might be easier to start with a more translucent one, with a similar hue/color.

Artist paints have the level of transparency printed on the packaging. Modell paints are bit more difficult, you need to find out yourself. You can also rely on the pre-selected sets /like Vallejo skin set, assuming they have chosen the colors with the right characteristics/.

The reasons why I keep mentioning the quality of resin
- reaction to thinning
- painting minis, we beginners, might quickly reach 20+ very thin layers on top of each other, and the paint will be as weak as the weakest layer. Looking to the more experienced painter’s tutorials, they get to the desired visual effect with significantly less layers, and acryl polymer strength is not an issue anymore.

This is the time we shall mention about a common issue, paint pulling off. It might happen when
- the layer below has not dried completely yet and reacts to the new amount of water /kind of re-wetting effect/. Or, the binding power of the resin is building up trough the drying process, and it has not reached the required level of adherence yet.
- the surface is too glossy, contaminated with fat, oil etc
- using too much retarder medium
- overthinning the paint
- the acrylic resin is just low quality
- any other reason I might skipped

While I have no way identifying the ingredients in a paint, I would separate acrylics how they behave during pulling off. The vinyl kind of behavior is when the paint pulls of like a rubbery film. The acryl polymer type of behavior when it pulls off in a smaller particle. As a side effect the vinyl kind of paints usually can not be sanded, because if you break the film, potentially the whole layer will pull off

Please note this is still not about describing painting techniques, but more a background helping to put them into the right context.

So far we have not mixed any color yet. In the next part we will start mixing.

ps> Please note I am not associated with, sponsored by any of the recommended companies above. My recommendation is based on my own experience /subjective one/

Thank you for the remark. I have changed the text accordingly

I have seen acrylics in tubes. Does this react like oils in terms of blending and drying? Thanks.

No, they're still acrylics. It's just a different delivery system than a bottle or jar.
Prost!
Brad

Thanks, Brad. I was hoping to get the best of both worlds.

Brian

Janos, You brought up an old memory from my childhood when I saw your name.....maybe you are destined for notoriety in the art world.

http://greatbutforgotten.blogspot.com/2010/12/jon-gnagy-tv.html