A possible way to make that helmet stand out a bit more is to turn it more bell-bottom so to speak. The bottom could be rendered slightly wider and more ergonomic when considering the shoulders and chest. Think of a bell for the shoulders, but the area for the chest and back is hammered back down vertically to fit the chest.
I'd love it if we could have that suit in full in the game, tie it to a quest and make that the only way to achieve it (Rewarded to you by a retired soldier). Now if I'm being historically inaccurate have a go at banana spammage ;D
Regarding making shield stick with armor, there's a small issue: Armors act as a damage reduction in that particular area is hits, but you can't make the game understand the use of a shield on the armor, and it's not possible to defend while attacking, although it could actually be moddable (holding right mouse button for shield defense and left mouse button to attack at the same time) but I'm not holding my breath on that. You'd need a condition to check whether you have both held down, or either, and make sure no messups occur together. How that would graphically happen, I have no idea xD
But allowing a dual wield of a shield and bow is fairly easy by setting the bow to be one handed, and remove the flag that disallows shields.
You have great modeling skills, keep making more