I agree w/ the OP 100%, NMs outside of abyssea could use an adjustment. It just seems a little silly to me when abyssea's NMs have marginally better things to drop, even considering the current level differences compared to the old days. Then Abyssea NMs take all of 3 or 15 minutes to be able to spawn again, whereas with older NMs one can wait up to 6 hours with no results. This is a little crippling on players' schedules, granted most old NMs are obsolete...until you consider Trial of the Magians.

"They respawn fast because Abyssea has a time limit" doesn't really hold water with me...unless you're just starting out, chances are you have a gajillion traverser stones on hand, maintaining your time is as simple as warping out and retrieving more stones, then having Horst or whomever return you to the scene instantly. The time limit is a non-issue for most people. It isn't like Dynamis or Limbus where you actually have a risk of getting booted then can't return until the next day. (3 days for Limbus, which will also hopefully be changed in the near future.)

Please consider changing non-Abyssea NM's spawn rates, SE.