A.) The climate is favorable in the mountains, and air conditioning is everywhere.
B.) The Muslims are confined to certain islands which I would not travel to.
Why not? Basilan, Jolo, and Tawi-tawi are nice islands. I was posted in southern Mindanao for 6 months and never had a problem. Many of those "terrorist" groups are more like punk kids than a serious threat. The big issue is the piracy and illicit trade route through the Sulu Sea.