Looks cool however I don’t like that it needs to be setup with a super-user and that it’s limited to your three predetermined access roles. I have a project in mind where this tool could be useful but everything is built with row level security policies and roles, the database includes sensitive data and authentication user for the connection have basically no access by itself, so it looks like Mathesar wouldn’t be useful here.
I also know of another similar project heavily utilizing RLS where end users actually have a 1:1 database user with access to their own data, here something like Mathesar could be nice as well if it would play nice with ACL/RLS.