We really desperately need a sort of consist editor to allow multiple variations in different stock. For example being able to put new loco downloads (regardless of route it was intended for) onto custom stock. I'd love to be able to put Class 37 with some Mk1s that I have from the WSR. If its in our paid DLC library we should be able to mix and match as we feel. At the moment, some railtour consists on the East Coastway is not available in our custom scenario creations so a consist editor would be a great addition to the game.