I tried a few: runbox, protonmail, and fastmail, and ended up staying with fastmail. The web interface isn't pretty but is functional and the service has been great so far. Very easy to set up with my own domain.
I've been on fastmail for a while too an I'm quite satisfied. Yes, web interface is ugly, but I use a mail client on my computer most of the time (mutt!) so it doesn't matter that much for me.