How many of the things I mentioned above have "some basis in theory?"
Genesis = advanced terraforming
Magic blood = genetically engineered blood
Black hole time travel (and other forms of time travel) are based on theory.
As far as unlikely things like Thaleron radiation or red matter are concerned, we don't know with certainty that those things (or something similar to them) can't be discovered one day. We do know however that the center of the galaxy is far too dense and active to have a habitable planet in the middle of it.
http://en.wikipedia.org/wiki/The_Physics_of_Star_Trek
Advanced terraforming in the form of the Genesis device is a massive stretch. Genetically engineered blood bringing people back to life is a massive stretch. Time travel through a black hole and red matter is a massive stretch.
It's also a massive stretch to think that a bizarre phenomenon or extremely powerful alien could create a calm "eye of the storm" area where a planet could exist and support life near the galactic core.
Just as much a massive stretch as any other Star Trek semi-magic. Let's not get carried away here just trying to prove a point. Star Trek has boatloads of fantastic crap. TFF is absolutely no different. That's not a deal breaker for people. If it was, the show would have died a LONG time ago.
Besides, the point being made is that this "unrealistic premise" is why the movie failed, and that's not correct. I can think of about 15 reasons that would be more obvious, realistic, and probable than someone saying "I'm not buying a ticket for that movie, because the premise of a life-sustaining planet existing near the center of the Galaxy is improbable." Thats not what 99.99% of the movie going audience looks at.
If you say so. The movie completely lost me when I found out what they were trying to accomplish. Maybe that is just me.