I think you've got a few really cool ideas and designs here which are let down by some really low-resolution textures and (in the case of the cape) models. Make sure you're utilising the UV space to the best of your ability and have a read through the character art and texturing guides which Valve has released.
finsihed this one :D It was a fun challenge haha, I hope its good enough for the game! http://steamcommunity.com/sharedfiles/filedetails/?id=157057557 here's my texture, if anyone is curious about it lol