Man, Obi-Wan really kinda wasted his potential as a ghost, huh? I mean - all he does is give the occasional bit of advice to a kid and talk to a swamp Muppet. You're a ghost dude! Think of the endless potential you have - you're non-corporeal, you can instantly teleport ANYWHERE IN THE GALAXY, and no one can hurt you now. There's one thing you should do ASAP:

Haunt the SHIT out of Darth Vader.