In my opinion, interacting with the game world in PVE style through IG quests is a type of roleplay. Therefore, my suggestion is to award one RP point to all characters per quest retro-actively, and to add RP rewards to existing in-game quests as time permits. Smaller RP perks could be gained this way as well. Thoughts? Issues? Thanks for your consideration.
Example 1:
Character X has 27 quests, and receives 27 RP points. A simple command could be used to trade quest count for RP points so the IMMS do not have to do it manually for each character.
Future quests may have rp rewards, but only rarely and only for big quests. Perks are similar, and we're currently discussing a sort of high-tier reward that's similar and an alternative to always giving items.