Straight giving exp to other jobs, no thanks. It's bad enough imo that we can level a dps to 80 and at the same time get a healer to 80 without having healed. Doing this to other jobs would be very bad.
I would be in favor of putting the exp towards something like a rested bonus, or the exp adding to our rested bonus. This means people still have to play the job to get the exp.