You're pretty much on the right track, everything is looking good. The animation is pretty nice, though I think the shoulders going up and down is a bit much. I made a quick edit to show a few things. The AA on the sword isn't working. You could definitely cut back on the colours and focus on nice clusters instead, I think that would suit the style better. His legs are also a little short but that's all up to your stylistic preferences. Consider working on a neutrally coloured background(I just use 50% grey), this is all fine if the piece only exists on pure white but any outer AA is going to fall apart on a background.
I'm having a hard time reading the second guy, is it meant to be like a bird/man hybrid? I'm sure that would come across better in motion but as a still at this size there's not much to say about it except try to use bigger clusters in your shading, don't have it hug the edges so much.
Not much else to say except keep drawing