Freight Trains and Cargo Ships

[AnnieGreenThumb]

I have several of my neighbors who seem to be regular players, but always seem to forget to boost my trains. We can now mark ourselves as unavailable, and those I don't send my trains to. Can we get a way where I can mark my neighbors like that, good only for me and until I remove it? Maybe a red flag on their little window or some such. Just a suggestion. I've tried making a list, but that's kind of clunky.