[sethrin]

Alcubierre drives require exotic matter which is not quite ruled out by the laws of physics. Hopefully they don't require Jupiter-sized masses of the stuff, although some have suggested as much. However, that solved, there are two slight problems with this idea. One is that FTL inherently violates causality, which is sort of a problem. The other is that the spacecraft is expected to pick up and accelerate with it basically any matter it runs into along its superluminal path, releasing these as a spectacular shower of near-c particles whenever it stops. Your other speculations have their own defects, but I'll let others address them.