This one is probably far out there, but we can dream can’t we?
One of my other hobbies has been virtual model railroading. Some railroad simulators have route editors where you have the tools to go into the program and create your favorite railroad. You can place tracks, roads, trees, buildings, and import terrain profiles. If you could do that with Zwift it would probably be a big hit with folks. Everyone has their favorite ride, with their favorite curves and hills. Plus, there are thousands of mountain and other epic rides that the creators of Zwift will never get around to modeling. Having a community of people making routes could be boon to the program.