I have to second Sams Tour - a great outfit and they do a good job of matching up divers with equivalent skill levels. Blue Corner is a must do dive - just hook in and watch the show.. For something different theres a small 3-chamber cave just opposite the jetty at Sams that provides a novel little dive at the end of the day, and theres plenty of mandarin fish outside the entrance at dusk. You can see sunlight from the end of the cave - so its not partially difficult. One of the best dives is one of the least known: Devil Ray City an easy shallow channel dive up the west coast - although only 1 or 2 guides at sams appear to know where it is. You just sit on the bottom near a cleaning station and watch the mantas hover a metre or two away from you. I remember counting 5 mantas at the one station
If you are starting to feel adventurous after all this and have good buoyancy skills and a safety sausage, then try the Peleliu Express: a great dive for those of us who can't be bothered finning.
Sams is who I dove with also. I would stay away from Peleliu if you are not used to strong currents and adept with a reef hook!!! Blue Corner is a dive not to be missed but try Ulong Channel or Siaes Tunnel, Nugelese Wall a few times or the dive metioned above. The Pyramid Butterfly fish always faces into the current(white triangle over body rest is orange and a dark face). They are everywhere there if they are looking down means up current along wall... one moves out from wall where current is less. Devils Point might mean more to the DM's, I went there with 3 of them on their day off looking for new spots and there is nominal current, we swam with 9 mantas at once. Wrong tide though so viz was not the greatest only compared with the rest of the sites. I was there for 1 month so got in with the DM's. Do the kayak trip, you see the caves where the stone money was quarried,snorkel,Japanese bunkers on the rock islands and a bunch of other stuff, perfect way to off gas. Have a great trip!!!