Is anyone interested in building a new email client/service based on the inbox-as-a-todo-list paradigm? Maybe something that would work with any email provider

Is anyone interested in building a new email client/service based on the inbox-as-a-todo-list paradigm? Maybe something that would work with any email provider but would sync todo/done/snoozed state with our server. Or perhaps could embed that state in IMAP flags. I'd be open to working on the backend and arch if there's interest.