Originally I had a plan to add a quick profile switch button with shortcuts, so it's easier to switch users right from the desktop, with a single tap (and remove other profile switch options from settings/notification drawer). But the problem here is getting OS autoupdates - you need to rebase changes and rebuild your GrapheneOS from scratch every time an update comes out (and I suppose possibly reinstall the phone from scratch, possibly wiping up all your data and profiles, then restore all this data and profiles), to keep your phone secure.
Which raises a question - is there a relatively easy way to get own builds update over the air, from own server, and apply incremental changes?