This should help show how the team is visualising the helmet and soldier design to be, a merge of real life soldiers of around the time our trailer is "made" to the elegant designs of our favourite space travellers.
An additional find to add would be that of the Space Marines in the world of Warhammer. I have been designing the Soldiers to be more like regular men who have signed up as opposed to specially trained dedicated soldiers. This is a reflection of the 1950's and also of the situations during the second world war. I have spoke with a collegue of mine and we feel that it shouldnt matter, the soldier can be bigger, tougher and ready to fight.
Here is a short CG film of the Space Marines in action from the game Warhammer 40K.