He can have alot more hair added on, try using a referance picture from the manga to follow as you draw. The shoulders should be larger, and watch how much you make them slope down. Remember to follow male proportions, don't make his body too thin or small.
Sorry to sound harsh but, The eyes seem tilted and head seems different compared to the eyes. The hair needs to be longer, and he doesn't need to look that skinny, i'm sure he's got some muscles from working those chakrams lol i love the smile though lol
LOVE the facial expression - he truely looks like a vicious character, it's wonderfull! :3 Someone pointed out the hair which is part of his trademark.. Unless you intended for it to look more "polished buisness type-ish", the hair should be spiky beyond reason. It's wise to check out how other people draw him to get a fair idea of how he looks like. I just wish you added more to the body - the head and neck looks pretty fine, but they're too big for the current body size.. Make the chest area a little larger, they are usually wider than the head in real life. Lenghten the distance between the neck and shoulders as well. It's only the size that was off imo, the build up of the body itself was very good. :> I like the sketchy style, adds to the character in a way.
Axel has tiny arms. I think it's in proportion myself...He's not supposed to look like an average guy xD; I really love his facial expression too; you really captured Axel right there. He looks like he is smirking at Roxas or something silly like that. I love it! :') Keep up the lovely work, I'd like to see more.
ZOMFG! Hottness in pin dude! xD I really like this drawing! He looks older but more handsomer! xD You did a really awesome job with this piece of work! But I think . . . .you need more hair on him, xD