These are some different armors that I found, Tony actually has a room full of different armors that we won't see. http://www.the-trukstop.com/articles/2008/images/ironman/silvercenturion
I would imagine War Machine for sure, as for any new versions of the Iron Man armor, maybe a newer version of the mk 3, I doubt they will delve to deep into environment specific armors ie: Hydro-Armor, Stealth Armor or Inferno Armor.
so don't fix what ain't broken.
Yeah, I think there's little chance of it being 5-6 years later.