For RTS I can highly recommend Beyond All Reason (BAR). It's very similar to Total Annihilation or Supreme Commander and runs on a very performant custom engine. And the best thing: it's free and open source, even though its still in active development it already has quite a stable playerbase and is extremely polished with a ton of qol features.

A good practice for drawing people is figure drawing. You try to capture the essence of a pose or a movement in just a few strokes. It helps immensely on gaining an understanding and feel of natural motion. Line of Action has a huge set of reference pictures and decent customizability. Link: Line of Action

I already did my part, but might as well spread the word among my friends.