I wonder what you don't like about "groups.io" Its pretty much a pure mailing list?
Like all of the webby time-wasters, they don't have easy to mirror zipped archives, because they want to to spend time hovering around clicking on their sites. http://www.classiccmp.org/pipermail/cctalk/ The one thing I would change here is removal of the restriction on attachments. Well, two things.. Getting rid of the cctalk/cctech split as well.
