I don’t think so.
Probably, but I wouldn’t recommend it. With FP1 some custom launchers weren’t able to update the OS, if the same is true for FP2 you’ll need to set the FP launcher as default before you update. Also I don’t think that having the FP launcher installed interferes with other launchers.
I’d try another launcher from our list. E.g. Buzz Launcher is very customizable.