About a month ago I moved my email to @soverin@mstdn.social. Having been generally happy with their service, let me share the reasons that I picked them.
* Both the company and their servers reside within reasonably friendly countries.
* Good old-fashioned IMAP+SMTP client support, with individual app passwords.
* Sufficient TLS and DNSSEC that I can require SMTP STARTTLS using both MTA-STS and DANE.
* Powerfull and flexible mail filtering built on top of Sieve.
* Full IPv6 support.
