I have a couple ideas that would be pretty easy for the Philadelphia area. The first the Frankford L, it has a mix of above ground and elevated. It's also broad gauge which would be very different from anything else is out there. This line has lot's of services and pretty much runs all day long. The other idea that I have is PATCO, which features the Ben Franklin Bridge. This Bridge services both motor vehicles and the train on the outside of the bridge. The other difference is that this line uses automatic speed controls, featuring some amazing BUDD railroad cars and you can also drive in manual mode as well and the railroad encourages that. Both of these would be pretty easy to do, and the buildings in the different parts of the city would create some amazing scenery as well.
