Philly, and a ring of turf within say 75 miles of it, for those of us who have traveled frequently, tends to have the most expensive lodging costs , hotels , even a cheaper super 8, will ALL be upwards of 120+ dollars on weekends, with nasty taxes. Maryland is too close to Conover, ie SELEM. Unless you can rent a scout camp with cabins some place, you have three costs, 1. A Medium to Large Hall with decent power, II Lodging, III travel by car, as most will want to bring their gear.
Perhaps the best way is to see whom wants to go, and start drawing rings of increasing size around their home base locations, and see where the most collide.
More like move up to Reading or Harrisburg. Delaware water gap area has decent facilities.
Steve