I am currently in a rather difficult situation whereby I want to save space on my computer and TFW does take up quite a bit of storage space. I have just thought about uninstalling routes that I no longer play but doing that would mean losing out on trains which help to layer up other routes. For example, I rarely play Great Western Expressway anymore, it's old and just not appealing to me right now. If I uninstall this route though, it means I lose the 165 which is a great addition to the London - Brighton route as it provides a good number of services around Gatwick and Redhill areas. Like most people, I don't have infinite storage space and more needs to be done so that we as players can save storage space, without losing out on layers on the routes that we love.
I second this. They've done it for loco DLCs, why not extend it to all trains instead? Can't be that hard.