I'd recommend Rackspace. $3 per user per month, and allowed me to bring my own domain. Haven't had any issues after setting everything up.
I tried registering this domain through G Suite and Zoho first, but they both said my domain had a TLD that's commonly used by spammers, and refused to bind it. Zoho eventually made an exception but took over a week for them to get back to me.
GMail's de-facto monopoly on email (and especially spam filtering) is a threat to the Internet.