As the subject suggests, I would like to host my own email server but last I checked my ISP blocks port 25 (though I haven't tried with port 587 but imagine that it's probably the same). Personally, I would understand if this was a premium feature on top of the VPN service, or a separate thing -- I really don't care how it's done, as long as I'm aware of any ToS used to implement spam filtering to ensure that the IP addresses that we'd be communally using to relay email traffic to our own servers doesn't get put on spam filters. Some services seem to reject the mozmail domain when trying to sign up with it and I'd rather be liable to Mozilla for spamming on their network than letting Google or someone else continue to host my email and personally be able to manage the DNS/email stack.