We stayed at the Reef last summer mostly because we weren't sure Compass Point would really be open yet. So we just looked around Compass point when there to dive. You've already summed it up pretty well, Reef is a nicer place to hang out. More resorty, nice freeform pool, hot tub, beach bar, big beach and you can stroll the beach for a bit in both directions (in front of Morritts one direction, the Reef condos/construction the other.) Pretty nice snorkeling off the beach. At the time anyway, thought the restaurant stank and service was worse, food at Morritts was better.
Compass point is quite nice but a more functional sort of place. Small beach but it's certainly a place to sit, don't know what swimming/snorkeling is like off their beach. Pool is functional, more designed for dive training rather than a place to relax by a pretty pool. Don't think there's a hot tub. Certainly a very nice dive hotel, though it needs some character - like a beach bar to hang out and tell fish stories or something.
The most important difference may be the convienience for diving. We only did morning dives (didn't think to book afternoon ahead, and they were full.) They took care of our gear very well and getting picked up to dive each morning really wasn't much trouble, and we had a nice resort to hang out in the afternoon. If I was diving in the afternoons as well, going back and forth definitely would have been a pain at best, rushing back and forth and trying to get something to eat.