If you are really into the pool aspect, Ramon's is hard to beat. The Palms, while right next door to Ramon's and a better value for the $, has their pool behind the building. So nice and private but not on the beach side so no views. Nice lush landscaping though. Basically the beach is the same for both places which is small but nice with relatively clear water. Ramon's has a wider section of beach and lounge chairs which the Palms does not. Both are great location within easy walking distance to town.
I have seen all the other places too and all are very nice. Caribe probably has the best beach but is by far the furthest from town (free bikes though
). I stayed at Xanadu on my last trip and it was excellent. Narrow beach but great pool and swimming area off the dock. Spacious suites. Free bikes & kayaks for guests. Mata Rocks has a small pool and beach area but very nice rooms & suites, friendly helpful staff & great little beach bar (also free bikes). Their oceanfront jr suites are the closest to the water of any hotel on the island! There are restaurants within walking distance to Xanadu & MR but not Caribe (except their own).