Yoda says that Qui-Gon has learned the path to immortality. It's almost Sithy verbiage, just without the demonic undercurrent. Calling it immortality and making it a long-undiscovered secret tend to imply that it differs from communication from the "other side". Yes, and the Annotated Screenplays tell essentially the same story - that Anakin passes through the netherworld before returning as a Force ghost. That bit is also in the script. If they're anchored to the Force, assuming the Force isn't going to be destroyed anytime soon ( *looks around nervously for Kreia* ) they should be good. You seem to propose that the Exile is a lightside version of a Sith spirit. But do such things exist? But we're not told that Force ghosts have "ascended to heaven". It is only said that they passed through ( or returned from ) a netherworld, which sounds like it would be somewhere south of heaven. Force ghosts aren't "dead" in the spiritual sense either, no more so than a Sith spirit; the ROTS script calls it the ability to merge with the Force at will, and doesn't make it sound like suicide.