Feel free to see my helmet.
1) are you 405th?
2) what did you use for a visor?
3) any other cool stuff?
For the visor I used a smoke tinted Vforce paintball mask lens
For weatering I dry brushed on the silver on areas that would get scratched under normal use, also chiped off the paint in the areas where the helmet may take that type of abuse under normal use, and to make it dirty looking, it was blackwashed with a black acrylic that was watered down allowed to dry a bit then rubbed down to where it looked ok
as for any other cool stuff, all I can say is patience when working on this stuff, I have built quite a few helmets and props so I have made alot of mistakes and how to avoid them, it just takes practice, I am building another Reach EOD helmet at this time that is more game accurate to make a mold of so I can cast it