roll your own DNS sounds like a great way to incur pain

unless you're doing it for a lot of people and have dedicated devops, I doubt you could do it well and keep on top of it in order to have nameservers that are both good, fast, and always up to spec without causing issues

Seems about right. I went with forwarding the domain to the server, although it needs to be done for each subdomain too.

best way is to pay someone to host your email. It is simple to set but fighting spam is a big meh

ok, "simple" but I succeeded in my second attempt, so can't be too hard

and btw, spam can bring down your server if it fills the HD, so spam fighting is not just a "nice to have" thing, and I saw servers which went down because of spam.

Now days you probably get much more disk space than what was then, but still it is something you might have to handle

I'm considering these in mind. Still, I have trouble receiving emails, while I can send emails.

Understanding the way linux manages the accounts and virtual accounts in a bit difficult, when it comes to managing the mail server

yes configuring the emails on the server is the hard part. I was lucky and when I realized that it is a bummer to do it, google still let you have gsuite for free, so just diverted email there.