If you have no issue with Google's services other than wanting the assurance that you can get support and are treated like a paying customer, I recommend GSuite. Although I'll (hypocritically, since I don't use it) still recommend Fastmail anyway since I think GMail needs way more competition. I'll let actual fastmail users convince you there :)
And Gmail needs more competition than just FastMail - so make sure to look at RunBox and Zoho. I pay for both and both are excellent services, having switched from FastMail after their huge pricing shift a couple years ago.
Zoho's webmail is currently much better than RunBox but the latter is undergoing a beta test of a new modern interface.
