Think wheels and tires.
wider tires would be good.
I would not worry about the frame.
wheels may perish faster with how you have explained it, to extend the life of them-
"Ride Light" lift your weight off the saddle just a bit when you encounter railroad tracks, or observable distortions of the roadway. Avoid potholes. (with the duration at work mentioned, be sure to have decent lights, I have one to illuminate the roadway, the other set to flash, drivers see the flashing lights, I see with the steady light)
Eventually the saddle lift will become second nature. Letting the bike "float" under you over tracks just makes is so much easier on the bike and your contact points.
With any purchase of a new frame set, drop the fork, remove the crown race and inspect.