Agree 100% with awayIgo. No need to look for Jewish communities, or lack thereof, to find suitable, or not-suitable, destinations.
As for PHL, this has been exhausted ad naeseum. PHL wouldn't work for LY because the O&D traffic isn't there. US used it for connecting pax, but LY gets that from JFK, EWR, and BOS, so PHL is just another destination. Plus they have no network to use from PHL, making it have to survive on the O&D traffic that doesn't exist.
For those in PHL, they can drive up the turnpike to EWR or they can connect in JFK/Europe.