Since you requested some info on PI diving (funny I did not see PI listed in your OP list!
), here is what I know and have done:
The months you mention March and April are considered HIGH season in some parts of PI. This is the only time (end of Mar-June) when the liveaboards do Tubbataha In the Sulu Sea, a world heritage site. I have never been, due to my schedule in PI, but hear it is wonderful with lovely reefs. Certainly something to consider.
March - May is also high season for places like Anilao where I have dived the most, (and am going to in 2 weeks time for a 1 1/2 week vacation). Mar-Apr will be quite busy in Anilao, as it has the best weather, and that is when all my pro friends/photographer friends book, usually a full year in advance. I have been 8 times, and upcoming trip will make it 9 times, (planning trip #10 for Feb 2010). Fabulous place for macro photography, and it is full of fabulous nudis, and critters found in much more difficult to get to and $$$ places in the world, such as Lembeh (not so hard to get to, but $$$) and PNG (both hard to get too and $$$$). You will not see any big fish, though. The reef is quite healthy and there is plenty of variety. Most trips I get to dive a new place I have never been to, and is not on the dive site map, as my operation does exploratories, and keeps them secret as long as possible.
I also have been to Malapascua (home of the thresher sharks) two times. I did not get lucky enough to see them up close, unfortunately, and the rest of the diving there was good. The best place to stay there is Malapascua Exotic Resort. They have air con, hot water, and power for 24 hours a day. They have a beautiful beach, and the food was decent. They, nor any other resort (I think) has running fresh water. I bought bottled water, and made my own camera rinse tank.
Other places that are quite dive worthy include: Dumaguette, and Balicasag Island in Bohol. If you need entertainment, you can go to Puerto Gallera, as I hear they have lots of bars and girlie pickup places, but as far as the diving goes it is NOT as good as it is across the Mindoro straits in Anilao.
A new liveaboard in PI is called Philippine Siren by Worldwide Dive and Sail. I was on it's sister ship in Andaman Islands, and can vouch for the excellence of the boat, free nitrox, and delicious food. A plus is also free soda and beer!
and free dive gear (excellent quality gear). The boat is in the Komodo area now and is transferring to PI later this year. I have not dived the specific regions they offer.
Hope you put together a good trip.
Robin
Edited by secretsea18, 16 August 2009 - 11:43 AM.