We dived with Palau Dive Adventures in 2014, told friends who went and thoroughly enjoyed the experience, and are going back again this October, but with a large group of friends in tow for two weeks. There are some very economical accommodations in Koror...I would actually be pretty happy with this trip if I can make it work. Palau has done some amazing conservation work over the past few years and I'd be eager to see how pristine the water is. Would you have any recommendation on dive operators/accomodation? ...
If you have a whole month, I remember seeing something about PDA having a divemaster certification program - work and train to become a divemaster there. You might want to contact them and get details if working/diving in Palau for a month sounds appealing