I also used to use catch all domains for all kind of registrations and my form was <domain>@mydomain.at (e.g. [email protected]). That most of the time solves the management aspect, except for some special cases where several domains share a unified login (e.g. Google or Stack Exchange).

Anyway, I’ve changed to iCloud’s Hide My Email some months ago, as this is much easier to use and you have easier control on all used emails. You can even add a comment to each address in the moment of creation. Also disabling (blocking) single addresses works like a charm.