I migrated from fastmail.fm, very happy with it. I don't know what plus addressing is.

I have also used pair.com for my email in the past, they do a very good job of that.

I'm not aware of an email provider, other than google, that also does calendar synch. That's frustrating because it's such a natural fit, even though the two techs are different.

You could consider a shared hosting account on pair.com, and install/run your own calendar.

Edit: I think google must be fastmail's best source of new customers.