Currently thinking about either Tuta or Mailbox.org, but to be honest, I don’t even know many providers.
Something I do not like is limit on number of addresses with a custom domain. Mailbox is at least a bit reasonable with 50 on Standard, but Proton’s 10 on Mail Plus is disqualifying for me.
Tuta has unlimited number, but doesn’t support PGP.
So I plan to check out whatever you guys use.
Tuta is good, but you’re supposed to do the PGP part yourself with an application like Thunderbird. Anyway Tuta is E2E encrypted and will never support Thunderbird. Mailbox or Fastmail should be OK.