Yeah I think it's a good idea. I absolutely hate setting up self hosted email, so if I needed to self host I'd definitely rather pay someone to set it all up for me. It's like the best of both worlds: you get the security of self hosted without the pain of having to do it. Bonus points, you get xmpp? I personally dislike email, but the fact is you're stuck with it, and if you're all about your privacy and security, self hosting is the way to go.