I'd kinda like a G/S/C remake rather then a gen 5, or at least a return to johto after the elite4.
But that's off topic so...
More ghost pokemon. I'd like a ghost/steel and a ghost/dragon (another one, one is not enough, and I know about giratina origin).
And you can pick one member of your team to come outside of the poke ball and follow you around.
And dragon/fire. How has that now happened yet? And an evil team which doesn't suck as much as it's name. Team rocket, suckish name=suckish guys.
Uuuuh, how bout, Omega Death Construct (yes, O.C.D...), coolish name=Scary guys who DON'T train wurmples or suck. Well, ima go do stuff.