Take all the time you need! I thought it'd be something to consider, and it wouldn't be all that hard to work the NPCs into it. Like, you oocly cash in points for, say, a flying monkey because you feel like your character could use one. They could just find it in-game, or they could be approached by an NPC who gives it to them (maybe even anonymously or in exchange for something).

... Thinking on it, there could also be certain 'events' were there's a limited number of rare items 'on sale'. Additional powers (temporary or not), potions that have a certain effect, stuff like that.

... I am thinking way too much about this for no apparent reason, sorry for spamming you.