In standard Android yes, but on GrapheneOS has 1 (one) private space per profile.

Eagerly awaiting multiple private spaces so I can move everything to owner profile.

Negative, full-res photos with EXIF is not possible to access with rclone (due to Photos API limitations).

This is likely via silent updates of Google’s Play Services.

You’re mostly right – those names sound like overkill. However do note I have been using Bitwarden’s Name Generator (random noun + number) and I’ve evolved the scheme a bit ( it is now always ‘user’ and I keep adding numbers until the generated username is available ).