i'm often in sogod bay, and second centrals' recommendation of peter's.
the visibility is generally as good or a little better than puerto galera, but not as good as apo island, if that helps. in november the visibility goes down, but not coincidentally that is the time the whale sharks (usually) come in. although the corals were undamaged, since typhoon haiyan (yolanda) the sharks have been less predictable. if they are in the bay, and you want to see them, you will.
the macro is excellent throughout, and there are a couple of really good muck sites as well (malitbog especially). the wide-angle i would say not so much, with a couple notable exceptions (the napantao wall is one). napantao as well is very fishy, and the slope can't be beat for macro. it is hands down the best site overall in sogod bay, and dense with hard and soft corals. if you like night dives, the padre burgos pier is outstanding.
leaving puerto galera early, you can catch the noon flight out of manila and be in tacloban well before 2. if you have a van picking you up you can be in your room before dark. matters are much easier if you leave from cebu city - weesam just started a once daily fast ferry to maasin, but it departs late afternoon and you will arrive after dark. details are in an earlier post.
to do it justice, allow yourself at least 5 dive days (10 boat dives, optional afternoon boat dive or shore dive). peter's is always happy to add a third dive onto a trip to napantao, and if you are into it and other divers agree, ask and it shall be done.
south leyte is woefully under visited, and there are many things to be discovered if you take afternoons off. and have a rented 'motorcycle'. 3 weeks is plenty of time to move from pg to south leyte and probably dive a couple days at another spot in the visayas as well.
good luck! i would be very surprised if the effort disappoints.