There's one thing a cat or dog familiar can do that's special, you can Send to Forage and they'll go off for a while and bring back some random potion ingredient. But the only time you have to brew potions is for the aspiration, and you can finish that with 5 apples. So Send to Forage isn't a big deal, and having your pet as a familiar is mostly just for fun. Going to uni might be a problem, no pets in the dorms! You can Dismiss Familiar, so they just act like a normal pet until summoned again, I think that will allow them to stay behind with the rest of the household while you're in university. But I'm not sure about that part- going to live in the dorm splits you off into a new household. I don't know if their being your familiar, even if currently dismissed, makes them so they HAVE to be in your household. However, you can also unbind them as well.
