We already have arbitrary features (valor pass in the example above is not the lowest part of the natural saddle, but the only section which is less than YDS 4 / UAII 3/ SAC T6+) that are parts of routes. I personally feel as these have common names, and are referenced in guidebooks and local communities this is fine.
On this note, I wonder about tagging a SAC scale onto an xc pass feature to indicate it’s rating.
Would having the bottom of a route also be acceptable in your view, as illustrated in the first image in this comment.. I assume you’d be against the middle two “decision points” (I know someone that took a wrong turn at the second one and had to turn around and change his trip heh).