There are very few allowed areas besides the casino and marina village. We’ve done Atlantis through CS and through a cruise excursion, prefer to do it on our own. It’s a 15 minute drive, when we did it through the ship we just took a cab back anyway. The excursion (through the ship, CS, or bought directly from Atlantis) includes the water park, beach and Digs access. I think it’s around $200 pp through Atlantis or resort for a day. I don’t think it’s worth it with small children.