Agree with most of the posts here!
I don't know if anyone else had this experience, but for me it wasn't until my 3rd game that it really sunk in, 90% of what you do is cosmetic / makes no difference.
My first game, I really roleplayed the rise of cow-like bipeds. I remember fully exploring the continent in the creature phase, going for wanders in the tribal phase with my shaman, and enjoying seeing the same landmarks in the civ and space phase - 'that's where my shaman stood thousands of years ago, in the shadow of giant fossil bones'. Little things like that. I took some lovely screenshots of that game. I made some beautiful cities in the civ stage and just flew around my home planet in my first spaceship. Found the space stage tedious, didn't progress far:
My 2nd game, I made a flying creature which was kinda fun. Didn't bother progressing to the tribal stage.
My 3rd game, I didn't bother progressing much from the tidepool.
After that, I only really played around with the editors. It sat on my HD for another two years before finally being uninstalled, yet to be re-installed.