I have had a look and not found another post similar - however, apologies if this has been raised already. If it has I'll up-vote!
It would be cool to be able to use Route Builder in a Wizard-type flow where an end-user can specify a few parameters - distance, elevation, time/pace, exercise type etc - and a route is auto-generated for them. The route can then be downloaded to a wearable and the user guided through the route - like a car sat-nav - via voice-command over headphones.
The feature could use pre-existing user-generated data - "Segments" - to generate routes which are considered "good" - ie, popular with other users - in the area to better ensure user enjoyment.
The feature could then be extended with additional parameters - road/off-road; b-roads/a-roads; via local landmarks - in later iterations.
Feasibly, the experience could be encapsulated via male/female chat-bot which would also talk the user through the exercise (sat-nav) and ask questions post-event to build up greater machine knowledge & improve the feature.
The major problem I foresee would be taking into account things like roadworks, crime and other issues that might lead to litigation. :)
Cheers! Love the application!