Thanks for the suggestion Mistborn, and thanks to everyone who chimed in.
We've already settled on the XP rates and we're going to stick with them. The current number is balanced where we want it, and it's not something we'll be revisiting.
I understand that some character builds may take a while to make. If you don't have that time available, please consider other builds or enjoy the grind and the journey to your goals.
Appreciate the discussion though, keep the ideas coming.