I'm generally a Mailman user through all the open-source projects that require a user to join a mailing list before contributing to a project. As a user that occasionally contributes patches/PRs to random repositories, my mailing list subscriptions are short-lived because I always get more emails than I need.
To that end, I would propose a new feature for Mailman to allow the user to be more selective with the emails it receives.
The following scenarios are those that would work best for me.
thread are sent to my inbox as well. 2. If a user sends an email through the mailing list that CCs/BCCs me I get all the follow-up emails in that thread as well. 3. Maybe -- and this one is more of an idea than something that I would actually use -- a generated email in the mail archive web view for each thread, to which I could send an email and be subscribed to any follow-up emails to that thread.
For me, this feature would make emails more manageable, and have them behave like subscriptions to individual issues on issue trackers.
My Python is rusty, at best, but I would be happy to help implement this feature in Mailman.