That's pretty rudimentary work. My advice would be to respect body traits and shape as much as possible, which in this case leads to; more emphasis on details. Muscle lines, ribs demarcation, etc...
My second advice is regarding Ag's rules and guidelines. Though you're not forced to do so, I strongly suggest that you put all your work together on a single thread, otherwise, you might be perceived as a spammer and people may take less and less interest in you. Of course, it's but a little suggestion, you're free to go about the way you want ^^.
The first is cool, but the second is really weird(sorry). But you can also check my samus fan art, the topic name is "My samus fan art" Again, the first one is good.
The first one is a littel sketchy (pun intended ;P). It has potential to look nice, if you cleaned up the lines a bit. The pants (still on the first) seem to be good,but i can't say for sure because the left one looks as if it is just a straight line much like a small child would draw legs. But i mean it's still pretty good, i wish i could just sketch like that. I know you said dont mind the head, but it might be the best of the entire picture (apart from the large ear!), in manga the tops of the ears are about even with the top of the nose(the bridge) and go down to about the peak of the mouth. Also the eyes and hair are the main focal points of the character, so unless the ears are what you wanted to be what the audience focus' on most i would lessen their size. I know you said don't mind the head, but those are just my tips The Second one is ok, the arms are different from each other, the left one being longer and closer to arm-like.
But i still wish i could sketch like that :P, if i sketch it has to end up being done to look nice, a sketch is never a sketch for me, i clean it up erase extra marks, etc.
