What I meant by the helmet was it looks like you took a Tusken Raider mouthpiece and stuck it on the front of your helmet, which is pretty much exactly what you did. That just doesn't seem to be the best way to blend the idea though. Why would a leather-wrapped piece be on the front of the helmet? My comment about possibly using sintra was to remove the Tusken mouthpiece entirely. Craft a new mouthpiece out of sintra (or whatever) so it looks like it was made with the helmet. Keep the idea of the Tusken, but make it look like the helmet was build from the ground up to have that part and it wasn't something that was just stuck on.
Charlie