My random thoughts:
Personally, I don't like the Pugs offset at all, I think it is kind of an ugly kludge, especially for those of us who aren't running a rear cassette. I like dishless wheels, but when I take a dishless hub and have to build up a dished wheel because of the offset. In a perfect world for me, I would run a non-offset 135 mm frame and fork with my Shimano Alfine hub, if it were possible to have enough clearance from the tire.
Ditto on the BB. Running a narrower BB would be a HUGE plus for me, even at 6'6" I find the wide stance of the BB to be akward. Even an 83 mm would be better than 100, but again, with a singlespeed or internal hub setup I wonder if you could get away with 73 mm.
Personally, I would go with a 83 mm BB and then run 3-piece cranks like Profile Racing that let you fine-tune your crankarm position pretty well.
Is it possible to get by with a 150 mm rear end, or does it have to be 165? Seems like there are some nice hub choices at 150. King, Shimano Saint, Azonic, Syncros... Even Phil Wood tandem/disc hubs at 145.
Running the same OLD front and rear is a nice feature at 135, but not sure I would want to do it at 150 or 165. Like I said, in my perfect internally-geared world a frame would have 135 non-offset front and rear.
Looking forward to seeing what you come up with. Since I have such a wish-list, maybe I'll have to talk to you about an upgrade for my Pugs.