Ice hockey, neat! (I'm lucky to be able to get from one side of a rink to the other upright, let alone at full-charge with a stick, lol).
As for Knox, one of the Knoxies will be able to give you more info about it. But from what I've seen, it's a pretty sweet place (looks like Hogwarts, has a lot more old-fashioned traditions and formal dinners/balls and whatnot than most of the other halls), but I'd have to agree with you about the walk. 15-20 minutes each way is just inconvenient, although that said, there's a supermarket/small shopping complex like 2 mins walk from Knox, so the only times you've got to walk is to class/if you want to go to town.
As for Arana having 398 rooms, when you consider that HSFY alone has ~1300 people, and from memory HSFY accounts for only like 25-30% of first-year students... 398 rooms isn't much, lol.