Originally Posted by Mr. Dent
Because a domino mask looks silly on screen and doesn't hide anything. The Balaclava is consistent with Winter Soldier being a russian secret operative and actually hides his identity.
A Russian black ops would also wear a toboggan or helmet of some kind; not let their long shiny mane fly wild and free like frickin' Spetsnaz Fabio. Sorry, but the concept art in its present form looks totally, well, non-heterosexual, and the colors are far too reminiscent of the godawful New Goblin.
Hopefully, they'll give his balaclava and goggles a non-greenish color, and do something to wrap that hair up when he's on a mission.