Here is a page from a sample Avengers script I drew a few years ago for Marvel Comics.
I drew a few more pages from this script and I’ll be posting them soon. These pages feature Iron Man in this horribly over-designed armor which was not only a nightmare to draw over and over, it barely looked like the same suit when viewed from different angles. When it comes to designing costumes, I always recall the great Gil Kane who said that when he designed a characters, he made that character interesting to look at but also simple enough that a child could draw their favorite character!
Thor is decked out in the look he was sporting at the time which featured those sleeves made up of little squares. To me, it looked like his sleeves were padded. To me, Thor looks best when his arms are bare. Nothing ever beats the classic look to me. Modern artists like to emphasize Thor as a viking or a barbarian. I always preferred Thor as a super hero.
I lucked out with Captain America. This was probably the very tail end of Cap actually looking like Captain America and not a cross between a SWAT trooper and a football player.