Where we ended up was storing very little information in the user or app metadata fields. We only store fields that are directly used as part of the sign in or sign up process.
ie. things like an ID reference back to our local database users table, a timestamp to indicate of the one-time onboarding experience was completed, profile image URL, etc.
After trying several different layouts it proved easiest to store the info in our local database, as the rest of our application needed this information, and we didn’t want to be hitting Auth0 APIs for this information frequently.