I think that customizing your character would be a great addition to this game. Things like different helmets or a certain type of gauntlets or boots to work toward with some sort of unlock system would be great. Added customization could also help find group members in a crowded lobby.
If you supported this game with an certain amount you can already change helmet. So I guess there will be more that can be unlocked, somehow.
I would like to have customization too, but the gear shouldn’t stick out from the theme of the game/characters. I don’t want silly hats like in TF2.