10 compatible people fit very well on a 52’ cat. We have had fantastic trips with this many people, even on a 45 footer. It is all about the adventure, good people, and flexibility. We have also rented 2 dinghies, under way one is lifted and the other dragged. Who cares if you lose a knot? If you are in a hurry you should charter a power cat and smell the fumes for a week. Negotiate hard with the charter company, some will do this and others not. But a second dinghy is great, especially when you all are going snorkeling.