I use a lot of different paint brands and types; usually for different applications. Often the type of paint I use is determined by the color I need. For example, if I am building US Navy 1930s "yellow wings" planes, Tamiya Camel Yellow in their TS Spray series is the BEST match and goes down great.
I started buying Tamiya acrylics when they first came out in the US around 1983. They airbrush great and you can thin them with isopropyl/rubbing alcohol, or lacquer thinner. Their Olive Drab is about the best match for US WW2 armor. The common Testors shade is a modern aircraft color. Tamiya paints are very durable for weathering and handling too. The basic assortment of colors is a bit limited but there are many mixing formulas online if you want specific historic colors. Tamiya acrylics are not the best for brush painting larger surfaces, although they now offer an extender/flow medium that makes them brush paint much better now. While acrylic, the Tamiya paints are still solvent-based and brushing on a second coat can lift up the first coat.
Tamiya also makes an enamel range that mirrors their acrylic series. These are not sold in the US but are VERY good. The paints behave like pre 1980s US model paints - dry quicker, more opaque, one coat coverage, aren't sticky or gooey. I don't use these quite so much because of the somewhat limited color range and difficulty in obtaining them, but they are good.
Vallejo Model Color paints are my number one choice for figure painting. They make a vast range of acrylic, water thinnable, colors, including metallics. The paints are very thin, and a bit translucent so you can apply them in layers to build up colors, highlights, etc. Side ranges like Game Color, Railway Color, Panzer Aces, etc. offer more colors and variations of colors. I like the clear black grease/oil color in the Railroad range. Model Air is the Vallejo airbrush line. Myself, I hate these and think they are junk. To me they are too thin and when you spray them, its just like spraying ink or colored water. The finish is also not so durable. I prefer other paints for airbrush work. Model Air Chrome is not very bright either considering its called Chrome.
Alclad lacquers are the best paints for many metallic/natural metal finishes. The paints are airbrush only, but are easy to use and durable. The notion that you need special gloss black undercoats, etc. is largely untrue. Most of the colors can be sprayed directly on bare plastic, or any smooth primer not just black. Chrome and Polishes Aluminum do best on black, though. You can even mask over many of the Alclad metallics. Alclad also offers a range of color shifting car colors, clear candy colors, and clear top coats.
I like enamel paints but do not like the current, more eco-friendly, safer, versions of most brands. In the 90s, most companies like Testors, Humbrol, and at the time Floquil revised their enamel paint formulas. The paints became more syrupy and translucent, didn't dry as well, didn't cover as well, etc. as the old versions. You can take 1970s Humbrol Flat White and brush paint it over black plastic and get almost total, opaque, smooth coverage. And the paint will be dead flat and not sticky. Try that with the new Humbrol Super Enamel and you get a transparent streaky mess that is gummy and tacky for days. Testors is no better now for the most part. Testors metallics like silver in a spray can seem to never dry.
I have little use for the various $.99 craft paints like Plaid, Apple Barrel, etc. I want to like them, but for models they are not that useful IMHO. Yeah they are cheap but that's about it. You can get good results with them but they take more effort than its worth if you can use any other type of paint. Again they are not so durable either.
For clear coats I use Future for a gloss (I brush it on) and Testors Clear Flat lacquer for an airbrushed flat finish.
I have used the Testors Acryl Flat and found that, while it dries flat, can discolor some dark paints. I have a couple models where the black paint turned grey with the Acryl junk. The laquer causes no problems and dries dead flat all the time.