Captain America

So I recently posted a drawing I did based off of a photo reference of Sebestian Stan/Bucky Barnes. I later proceeded to draw Captain America, which was even harder then the Winter Soldier. If ANYONE is reading this, I'd like plenty of constructive criticism on what you think, if you're feeling up to it, of course. This drawing was fun and hard. I did a lot of erasing, shading and tried to get the depth just right. I think it turned out well, not to boast or anything...