Rolling stock & Gameplay suggestions

Gathering votes

A mail car, a locomotive, and a tender would be cool (I.G. k-37). Connecting the front of a locomotive to the back of a car without needing to flip either would be nice. Locomotives should be able to go the same speed backward and forward (for accuracy). Double heading diesels should be possible (with both running; maybe doing this makes them faster).

Edit: I completely forgot to mention we need a way to disconnect cars without breaking them.