SecureScribe I don't want to browse every shady alarm clock app that exist on Play Store
Alarm/clock apps should not need any permission granted, I think. You could install any app that seems polished enough, and if it doesn't work with zero permissions granted, leave a bad review and move to the next app.
SecureScribe I don't know if anyone would be interested, I will just keep the apk for myself if the main developers don't want this to be added
You can publish it without asking to incorporate it into GrapheneOS. Maybe others would like it.
By the way, you should have a look at this app at least: https://github.com/BlackyHawky/Clock
I've never tried this app, just seen it once somewhere.