I know this is probably totally unlikely, but LionChief or LionChief+ retrofits. A TMCC/Legacy to Lionchief bridge device to allow control of older LC and LC+ locos via the cab-1 or cab-2.
Down the road a TMCC/Legacy to TIU bridge to control PS2 and PS3 locos for those who are going to eventually be orphaned by the end of MTH. Even better, find a way to directly control PS2 or PS3 locos without a TIU by making some sort of emulator device.
A LionChief controllable culvert loader and unloader that works from the App and/or the universal remote.
How about a updated postwar Seaboard switcher with LionChief or LionChief +2.0?