Except for undercoating (priming) I've never used anything but oils for 40+ years.
Tried acrylics a few times over the years but always came back to my 'trusty' oil paint.
Obviously there are little or no pre- mixed colours in the oil paint ranges. It is all up to you to mix the required colours, but then again this gives you a 'freedom' no other paint can match.
Another advantage is that you don't need many paints.
A good starter palette would comprise:
Titanium White
Ivory Black
Phtalo Blue
Chrome Oxide Green
Burnt Umber
Burnt Sienna
Yellow Ochre
Cadmium yellow
Indian Red
Cadmium Red or Scarlet
Naples Red (reddish)
Later on you can still add what I call 'lazy colours' to avoid having to mix too often. For example Warm Grey and a Dark blueish Crimson are very useful.
Some of the paints are very opaque others are not. However when mixing them their covering strength changes, mostly becoming at least as good as the best of heavily pigmented acrylics. For example white is always a very difficult colour but when Titanium White is mixed with Burnt Umber and Chrome Oxide green (to give an unbleached wool tint) it covers black in one go. You can keep on adding white until it becomes nearly- atl least visibly- white again and it will still cover anything.
Some of the colours dry slowly ( mostly Reds and Yellows- but not Yellow Ochre that dries really fast) As such the paint remains 'workable for hours if not days. A godsend if you ever forget to clean your brushes.

As a medium for painting I use refined Turpentine, White Spirit for a fast first cleaning and purified linseed oil for the definitive cleaning. This will even get dried paint out of ferrules. Every two or three painting sessions I also clean my brushes with Brushcleaner soap and warm water.
Technique for painting is somewhat different. In fact there are several. Mine is - generally- to mix the base colour and liberally apply the paint then to remove most of it with a soft brush. After that it is detail work like shading and highlighting with the 'normal' smaller brushes
Almost exclusively use Winsor & Newton 7s with a few Rosemary ones for special jobs.
Of course the main advantage of oil paint is the wet- in wet blending of colours. Basecoat then when still wet apply the darker shadows and immediately highlight with the appropriate colour.
Normally 'warm' colours are shaded with brown and highlighted with white, and 'cold' colours with black and white respectively. Green can be used both cold and warm.
For special effects you can easily experiment with this. The darkest visible colour to the eye is very dark Purple, not black.
One last thing about that vaunted drying time. If at one point you need to speed up the drying process.... simply put the figures in a oven. After about a hour or two at 75° C even the most stubborn Cadmium Red will have -surface- dried enough to over-paint. It may take- depending on which paint brand you use for some colours to take up to 14 days to dry out completely. But by that time they will already have been long varnished and on the playing table.
