That's a good idea, I've only been painting for like a year or so now. I'm looking for better ways to make the details better, I've been experimenting with clear coats
Oils are very popular as all over tools because once you get used to them they are quite easy.
Just do any of your acrylic main colors and do a clear varnish. Then the thinned oil paint wash on top, a black or brown color. Oil paints take days to dry, so you have a lot of time to push them around before you’re happy. Then just wait a few days and varnish again.