1) I wouldn't worry about booking travel to Cebu from the USA. There are a ton of domestic flights in the Philippines that are super cheap and the flight's only an hour or so from MNL. You can do a LOT better than 1150 USD from SFO-MNL if you shop around. Well, except for the June-July and December vacation periods.
2) The weather at the time is hot and dry season, and the heat can be oppressively hot, tropical and muggy. The good news is that it's beach weather.
3) Your target dates are Easter week, known as Holy Week in the Philippines, and the whole country gets the days from Thursday-Sunday off. Hotels in resort areas will be ultra-high season priced, and availability may not be easy.
4)
http://www.asiarooms.com/ can give you an overview about hotels and prices.