I had a number of trains come up for renewal around 1946 and is seems there is a real lack of non-electric trains at that point in the game. In 1946 in particular, the only non-electric train is the Pacific A6 which is a mindblowing $1.06mil each. We could do with a smaller steam or diesel train in that space. I don’t necessarily want to upgrade all my tracks to catenary because some of my smaller steam trains are old.
I agree with this and had the same issue in 1907 when a new high speed steam train was released, the previous one was discontinued immediately and the new cost a lot more to purchase and the running cost was 3 times that of the older one. vehicles definitely need more overlap before becoming obsolete