See your problem. I guess the question is how do they want to control the switches?
If they are mainly running conventional and want to control their layout from the control panel, I think going to 2-wire operation is the best bet. You would lose the switch's built in TMCC capability. If they should also want the capability to control the switches through the Cab1/2, you could add a SC-2 or ASC to control the switches in 2-wire mode. This would complicate the wiring effort.
If they control their trains via TMCC/Legacy and they want to keep the 2500's TMCC function, I would see if they would consider taking the switch controllers off the panel and putting them on the edge of the layout near the switch it controls. For me, I walk along side the of the train as it goes around the layout, and use the controllers to operate the switches (except for routes, I find this easier than using the Cab2).
Good luck
