Malapascua compares very well to all of the above. The Philippines is primarily a macro destination so like Dauin or Cabilao you get lots of incredible small stuff - pygmy sea horses, Bobtail Squid, Ghostpipefish, Harlequin Shrimp etc. Unlike the others Malapascua has three recreational wreck dives. One is not great, one is very good - a broken up Japanese WWII wreck sunk in 1944, the final is the best wreck dive in the region - The Dona Marylin - a 100m ferry that sank in Typhoon Ruby in 1988 with a lott of loss of life.
Malapascua has a more varied topography then anywhere in The Philippines - it has kilometres of wall diving around Monad Shoal and Kalanggaman Island, it has much diving (sandy bottoms), it has caves and boulder like terrains (Gato Island), wrecks and coral gardens.
Dauin as you probably know is sandy bottom much diving, and very nice, with the add on option of Apo Ilsand for hard corals. Moalboal is all wall diving with the highlight at Pescador, and Cabilao something similar.
For the Thresher Sharks, they are easy tosee without Nitrox and most people succeed, Nitrox gives you extra bottom time. The section south where the sharks are at the moment ranges from 14 metres to 40+ so its hard to say if Nitrox is needed unless you know exactly your profile before.
The Sharks are there all the time and the chance in March is excellent.
Check out Evolution Diving when you get there, excellent place to hang out and dive.
