After some time, late game players have an abundance of perk points &/or Ascension Knowledge. It would be cool if they eventually had another use; similar to XP after 4x99, where it could be used to get you extra rewards or even be used to upgrade perks past their current cap.
For example: Something like resource saver- you could spend 10 perk points to get a 1% increase after unlocking the final tier (subject to balancing of course). So players with all the resource saver perks & say, 100 perk points, could get an additional 10% when crafting.
This could also be used to include AK instead & take 100-1000 AK to boost an artifact.
