QuoteThis falls under compromise area of the hobby. The available space issue.I second this response. One can also add that doing the compromise you add a puzzle to your layout. That is, having long train cars can add that switching puzzle to your layout. You have to remember that the long train cars cannot travel on say the "A" main line, but they can travel on the "B" main line. This is no different than areas where containers cars cannot be double stacked due to the mountain tunnels not having adequate clearance for them.
If space is an issue, then maximize the main line to support the long cars. Use the short radius for the smaller cars. One thing to note is that if you have plenty of short length cars, the puzzle is much easier to work with. If you have more longer cars than short ones, not so much.
This is my compromise.