Good timing on this. Someone on the WMR team at Microsoft (I’m thinking of Harry Potter with his under the stairs broom cupboard in terms of offices) is talking about a new feature where 60Hz can be picked without reducing resolution or FOV - sounds nice:
https://www.reddit.com/r/WindowsMR/comments/eovbc3/lets_talk_about_headset_settings/
Due in the 20H1 build of Windows, so dunno, maybe July ish for release?