-I think Psyduck should have a main ability that's like Truant, except it can't attack because of its headache. (I was considering this the other day playing bw2)
-I love walking pokemon, though I agree it should be optional. Maybe some minor interactions, such as praising or scolding your pokemon after a battle. It would really only affect happiness, I guess, unless they added more mechanics, but I would like to interact besides "talking" to them...aka looking at them.
-Water should be weak to poison.
-Getting he rods throughout the game again
...basicaly, Bellossom up there makes some point I like. lol.