As much as I agree that the first Spore did not deliver one even half its promises, I'd be interested in a sequel, provided that:
* acquiring traits and parts is harder and more rewarding, and that decisions made in previous stages affect you further along. I was overjoyed when I first got the electric defense-thing in the first stage, only to evolve legs and suddenly find it now provided +1 charm, and I was now defenseless.
* the tribal stage is re-worked. I once made creatures that were essentially velociraptors with wings, and yet a stone axe was necessary to win a fight versus kermit the frog...
* The civilization stage wasnt too bad, if a bit formulaic; what bothered me the most was, no matter the way you designed the vehicles, the only variables that changed were health, damage and speed. I tried to build an aerial armada of badass zeppelins for my raptors, and much to my chagrin the acted nothing like how they looked, acting more like dive bombers than airships.
* there are variable tech levels in the civ stage. minor gripe, but everything was equal to everything else, when there could have been so much Age of Empires/ Civilization-esque fun.
summa summarum: yes.