I was trying to suggest something that would avoid players trying to grind at dog-petting, and that kind of situation.
not sure there'd be much point. all you have to do is keep relations above zero to keep them from running away. at least that's the only effect i've thought of so far.
Also, why not have a spontaneous NPC triggered minigame opportunity?
its on the todo list. make NPC's spontaneously walk up to the player and engage in various dialog actions. on the todo list, one of the examples is "ask to go bowling" from GTA. <g>.
already in the game: when you encounter friendly cavemen, their leader may walk up to you and engage you in random dialog (exchange greetings, news, maps, trade, etc).
so that will be easy to add as an occasional AI action on the part of friendly NPCs near the player. and playing a mini game will be easy to add as one of the dialog options.
believe it or not i've only got 6-12 features like that left to do and the entire gameplay is DONE! nothing left but final graphics and help.