Excellent, thanks.
If you’re looking for things for your ‘to do’ list, the thing that would make this the perfect email plugin (for me, anyway!) would be front end sending for users. That does seem to be the feature that no other plugin does, or does very poorly.
I’ve seen a number of requests for it, and no elegant solution yet.
The requirement (for me, and the others asking that I’ve seen) comes from running a club website. We want members to be able to email all other members, without having to circulate an updated mailing list all the time.
Other than that, great work.