I'm gotta go against these options and give one of my own. Forget anything metal, chrome, nanites, etc. they need to make him "new and improved" for the movie. You know updated kinda like with the Joe/Viper battle-armor we've seen. Having said that I propose Destros mask be made out of a translucent crystal, and in the shape of and alien skull

Nothing bad can come from a combination like that.