evenhaim,
PBY's could carry vehicle or field supplies, bombs and torpedoes (Black Cat PBYs sunk almost 115,000 tons of enemy shipping). I think I've seen photos of the PBY with two torpedoes loaded under each wing. Her defensive armament would make her a tougher target for running supplies than a C-47. The PBY could be made available from ports, as well as from airfields.
Also, if HTC ever adds subs (which IIRC he wants to do) the PBY was the premier Allied ASW aircraft.
Additionally, the PBY would be invaluable for scenarios such as those set at Midway and Guadalcanal, and I can see her used in FSO in a similar "recon" objective similar to how Mosquitos have been used.