This idea may or may not have been expressed already, but a search on the idea didn't turn anything up.
With the museum collecting paintings and artifacts from other cultures, religions, and lands, seems like a perfect opportunity for an item-quest system. You'd have moral issues involved, in that some artifacts could be outright trespassing, such as the ruined temples in Har'akir. Or, a religious artifact could cause controversy, if leaders of that church feel that the relic doesn't belong in the museum. Also, it makes sense that certain artifacts would fetch a good price with the museum.