My greatest concern would probably be lagging and loading time. I built a 3 stories palace and the loading takes "years" so I can't really play it. I'd run into the same problem if building numerous community services on one huge lot, I assume.
Re sims running all about and family not using the hotel suite intended for them, on some community lots where I have a hotel, I simply don't have a door to their unit but teleport the family in there. That stops them from wander off, and other sims will not wander in. Btw, I use the Shift+teleport in regular game play too, not sure if it is a mod allowing it, or if it is in the game, though.