/cgl/ - Cosplay & EGL

I know it's been done to death, but I want my first cosplay to be a Ranger Vet from fallout NV.
However, I want to make a functional helmet/mask that doesn't need to look exactly like the one in game. I've currently got a similar looking surplus helmet on the way and I'm looking at voice amplifiers and any sort of mini air conditioner that I can add to the side of the helmet (like where the flashlight is, which can also be added).
Any advise for this sort of thing? also what do cosplayers do for hearing? should I bother looking into some sort of mic system so I can hear people clearly around me? I can possibly jury rig any electronic object to have on/off switches to a wrist band depending on the attachments I get and how they are laid out internally.