If development time = suck, then Chinese Democracy is going to be the worst album of all time.
The minigames in spore can be pretty fun (underwater stage, early land stage) but they did get a little tedious in the latter half of the game. It's like you spend hours upon hours developing survival skills for your creature only to have all our choices rendered nil once you enter tribal phase. In the end, 90% of the game is just the space stage as well (my favorite part easily) But the only thing that matters after all that hard work and evolution are 2-3 perks you've earned. Everything else is just aesthetic at that point.
The worst aspect of the game in my mind, however, is that you can flip flop at a whim betweem what type of creature you are, it only comes down to points. That means that even thought you're evolving, each time you go to the editor you can completely erase your creature and start anew, getting all your DNA points refunded. I had to alter my creature between an aggressive meat eater and a passive herbivore every 5 minutes in the land phase to maintain the middle ground I was shooting for.
It also seemed strange that the second you're done with the land phase, nothing... NOTHING you developed your creature to be matters at all anymore. Attack ability, social skills, all of it is immediately rendered useless and the only thing that matters at that point is what tools you're carrying. I personally would've liked a mental/physical slider at that point.
Once you reach the space phase, the game actually gets deep. Really deep. I think it's definitely the strong point of the game, but once again, the only thing that differs at all between any civilization is a few minor perks.
If there was one thing I could change with the entire game it would have to be the point distribution. If you choose a mouth that gives your creature +3 singing, and then also buy an item that gives him an additional +1 singing, you're total singing will still be 3. points don't stack, they just take the highest number and use that. Oddly, it's completely different for vehicles, where points do actually stack.
Edit: Just wanted to also point out that the first stage isn't at all original, there have been countless 'big fish eats little fish' games made. There's one for the PS3 that's pretty great and involves rotating the sixaxis to move, and a ton of flash games that are the same concept. Have to say there's nothing innovative at all in the game until you get past there.