Right optimized one looks best, because it's the only one that doesn't squirrel any of the big rooms (library, gym, cafeteria) away at the ends of corridors.
I think it's probably a balancing act between placing the big room at the end of a hallway (making that hallway a nightmare prior to any event) and placing it in the middle of the building (making that intersection a nightmare prior to any event). I'm sure it depends largely on the specifics of the room and how often it will be used of course. Less frequently utilized is probably better off further away from the center, more frequently better off closer but with multiple entrances & exits to ease congestion.