@ibj40 has mentioned the hot spots commonly recommended, Rincon (west side) and La Parguera & Guanica (southwest side), in threads on this topic from previous years. La Paraguera also has a bioluminescence bay.
I spent a week in Humacao on the southeast side of the island, pre-hurricane Irma, but had to go to Fajardo (east side) to dive. A dive shop in Ceiba, also on east side, didn't go out everyday as they had to have a certain number of divers and the only contact I had for diving out of Humacao was a guy who's boat was in need of repair, so he wasn't going out.
Diving out of Fajardo was, in my opinion, the least memorable diving I have done to date. I can't even compare it with anyplace else I've been to dive. Thank goodness I was spending a 2nd week in Grand Cayman - which by the way has a bioluminescence bay as well.
Would agree to disagree - Coz has places with good food but I have been to PR twice and the food was very good. Some very good places to eat in Old San Juan as well as where I stayed in Humacao.
+1 on this. Big St. Croix fan. Provides variety of dives (wall, reef, wrecks, pier!!)