Cool artwork, but I think you should ditch the anime/manga style if you want to progress stylistically. It's a very poor base to learn how to draw properly since it is too simple and unchallenging to provide a steady evolution. Also forget about the classic arms-open stances and start picturing movement more frequently. The best way to create a character is first to picture it in action. The essence of a character lies in what he does, the way he moves, and how that feels to the spectator. Different looks and aspects are easily adapted from this starting ground.
My advice for you is to start looking at classic 20th century fantasy & sci-fi illustrators for reference, especially those in the lines of Frank Frazetta and Ian McCaig, that is, if you really dig classic fantasy artwork and intend to keep doing it.