24 with non-terrorist attack as the core story would be great IMO.
Have NASA instead of CTU and the disaster is some kind of trouble on the space station. You could still have political intrigue with them trying to cover it up, and maybe the disaster is that it could destroy a city or something.
Honestly, anything would better than another terrorist attack. I got so sick of that after a while. I tried to re-watch 24 a while ago and I barely made it past the first episode, I was just so burnt out of the core concept of the show.