[charlieegan3]

I'm surprised to see so many suggestions for Office 365. The cloud exchange configurations for wildcarding and alias sending were very challenging at least for me to configure. I also found the mailbox export to be impossible to get working. These tasks were both trivial in Google (where I was migrating from at the time) and Fastmail.

I think that fastmail's implementation of custom domains and wildcard alias sending is the best I've seen to date.

That might not be a feature you care about, but I'd certainly consider Fastmail either way. Their domain DNS checklist page is really helpful and responsive in helping check you've set it all up correctly (DKIM, SPF etc).