I've been on both American SM's in the past year and although I definitely prefer California's, there is one small detail that Florida offers.
The bigwigs can feel free to tear out the old tracks, the old rockets, those dusty upside-down astronauts, and heck, even those completely irrelevant video screens that you can see yourself on as you head back out towards Tomorrowland.
But please, please, PLEASE leave the queue tunnels alone. The music in there is probably my favorite audio experience in all of WDW and even though it doesn't exactly make me feel like I'm out in outer space, there's something amazing about the quirky, somewhat creepy music they play in those dark tunnels. California's version just doesn't offer that aspect of the experience and I, for one, want it to stay!!