When I create composites, I really never aim to create something "realistic" talking about colors and lights, I always aim to do something more cinematic or videogame feel like.
I always do sking retouch first and then I do dodge and burn to make the model look more 3dimensional, then I create a smart obj of that retouch and start creating alpha masks for the compositing part. I repainted all the clothes as a excercise aswell to learn more about digital painting.