Originally Posted by
Salur
Are you sure you did everything? Including the bonus series for each planet? If I had to guess, I'd assume you might have missed the Nar Shaddaa or Alderran bonus series (level 31 and 40, respectively).
Again, I haven't actually leveled solo, so maybe I'm way off, but I suspect that there's stuff you missed without realizing it.
Thought of another possibility, actually: If you spent much less time on the fleet/ship than I did, you wouldn't gain as much rested XP. That could be it, I use rested EXP pretty much all the time.