+GP is meant for gathering from unspoiled nodes at 50, and endgame you will be focusing your efforts on getting your GP to 600.

However... to solve both problems... they should have made GP regen like HP and MP do... as a % of max GP. This would make +GP desireable and it would automatically increase GP regen without having to do any reitemization.

Currently its 5/400 per x seconds (2-3 seconds i think? i've never measured). So you should regen 1.25% GP per tick/swing instead of 5 static imo. At 600 GP you would then regen at 7.5 GP per tick. That sounds like the perfect solution to me!