Well there could be a couple things added to roblox
1) capes
2) gloves and boots
3) a new dominus type (the old ones are getting old :P)
4)sweaters
I have may more but here is my first couple. Feedback please!
Everything you listed can be custom made by players.
Capes, Gloves/Boots, and Sweaters can be shirts and pants. I know VendettatheGreat has these.
A new Dominus - well anyone can make one and they're everywhere in the Models section.