I have a group of 10 routes: https://cycle.travel/map/group/12335
The default display has the route list in an arbitrary date order. Click the sort button, choose by name, and perfect! Then showing all these other bike routes is total clutter. Change to OpenStreetMap, and perfect! But these don't get saved. And have to be set every time by every viewer.
My suggestion is for the system to remember what the group owner has last set these two options to, and that be what is used for everyone that clicks on that group link.
Having the layer selection be remembered for all routes would be nice. The routes are set. Showing other routes around are clutter. But we do care about the sites around. So for every route, the system could remember the layer the owner last set.