I'm looking for suggestions for an email host that includes IMAP access: my wife is very attached to the Gmail interface (web and phone), and so I need to cover that in the transition (and maybe convince her otherwise in the long run). That sadly immediately rules out Protonmail.
Bonus points for EU jurisdiction, and a mail interface that doesn't look like the 90s (for my use).
If EU jurisdiction is important to you, Runbox* and Mailfence are pretty ok - their service isn't as well-documented nor polished/reliable as Fastmail (e.g. I've hit some odd errors fetching large amounts of messages over IMAP - e.g. connecting a new client and blind first big sync of mail on an account with a large archive) but overall they're both extremely serviceable.
Re: mail interfaces, Runbox's is a little better than Mailfence, but both are a little dated. Again, Fastmail is better here; non-EU is their only fault imo.
* Runbox is technically not actually EU, per se, being Norwegian.