We didn't do any land-based activities, just diving.
I believe Rocket Frogs have some rooms for rent in their new clubhouse, but I've no idea if they've enough room for 4. We stayed in Los Almendros next door. Rocket Frogs are good guys. They typically run 2 tanks/day but will do 3 if you ask -- or you can take a few Al50s and swim around the rocks to the right and left of the beach (it's snorkelling depth there so an Al50 can easily last you close to an hour). The dives are typically deeper and colder (and shorter) than what you'd do on the Caribbean reefs. But the fishes are friendlier.
There's only one restaurant and all the shopping is in the next playa over, where there's also a couple of resorts and dive shops. I imagine most of the touristy stuff would be there too, so if you're looking for land-based stuff, that may be a better option.