Do not purchase a new saw until you've checked out the SawStop. You can see a convincing demonstration in the video below. The story is that the inventor tried to market his design to all the major saw manufacturers, and none were interested. So he started his own company, which has been pretty successful.
I breathed new life into my Craftsman saw by replacing the fence. I used a Delta fence sold at the time by Lowe's for about 200 bucks. This extended the rip width from 24 to 30 inches, making a huge difference in the utility of the saw. It's not a simple project to do the retrofit, but you can find instructions on-line from others who have done this conversion.
My Craftsman saw had a fairly decent fence, which I gave to a friend with an older saw. He was grateful enough to give me his old Craftsman dust collector. It's a big improvement over nothing, but if I were buying a new system I'd certainly go big.