Having started down this path of non-big-corp hosted email and my own personal domain (which is definitely not self-hosting, though I'd never want that inflicted upon me) almost a decade ago, I won't say it's been a rabbit hole. But there have been some learnings over the years — realisations, rather. The biggest: I went overboard with everything around moving my email away from Gmail. Almost like what I did with seedboxes over the years, until I realised I didn't need most of what a seedbox offers, and that I didn't need a seedbox in the first place.
Whenever this discussion comes up here, or say on Reddit, the focus immediately moves to privacy, anonymity, tracking. Those are valid points, no doubt. What takes a back seat, I suspect, are aspects like reliability and some sort of accountable customer support — and no, a smaller company doesn't need an army of support agents, just a few people and an intention to help and solve problems, delays being okay. Many utterly irresponsible hosted email providers get a pass just because they posture with an activist flag. The whole virtue signalling in this sub-industry muddles things.
Some are worse. Some deny you basic email access in the name of things like e2ee. Now e2ee is a fine idea, but enforcing it unilaterally — and yet not really enforcing it, because let's face it, you can't until you "move" your ecosystem, the way Signal has been "moving" it. Locked to the app, locked to the web app, yet your emails flow to other systems and addresses that aren't e2ee (as they should!). You just can't use IMAP, among other things. This has become such a toxic topic on certain forums that I start wondering if maybe I'm the one holding it wrong.
Another observation: bundling things that aren't email. This is another contentious topic. I wish there were more mainstream, custom-domain-hosted email providers that just did email, nothing else. I first started using disposable email designed to route to my domain via my mail host (a German one). It was as convoluted as it gets, and still is. Then came Apple's HME, with limitations I wouldn't wish on an enemy. Finally settled on SimpleLogin. Not the best, but what I like is that it gets out of the way — I can receive emails on those addresses and send from them easily. It's also a separate service, not hooked to my mail host, and I wouldn't want that now.
What would I do if I had to go back to when I was starting?
1. I wouldn't look for a "private" email provider — just get my own domain (which I did) and sign up with a better-priced, responsible, email-only provider (preferably something larger).
2. Never use the free email that comes with the mail host account.
3. Let go of privacy and tracking on email. It's almost painful to say, but I'm tired of that part.
And if Gmail hadn't done idiotic things like forcing "folders" on my account with no way to change or delete them (Important, and whatnot), I might have just stayed with them. At least my emails would have been delivered — unlike with my current host, which doesn't do "emailing" up to standard. For heaven's sake, just let my email through, and let senders get through to me as long as their ID is verified and they're not on any spam list.
Hell, I am thinking of moving a domain of mine to Zoho. A company I'd have never imagined thinking of in the same breath and it has not become "better" somehow. But here we go, a decade later. This is just a rant I guess. But I am really exhausted and yes switch mail providers even with your own domain is daunting! The apprehension of downtime, fear of losing emails, something breaking etc are just too much. But at least there's a possibility.
tl;dr: If I do it over and Gmail stayed what it was back then, I'd just go back to them, just with "my own domain." Not that Google got better; just shows how disillusioned I am with the personal-domain-hosting hype.
My own domain, nothing else. Not the rest of what I've done chasing for "this kind of" mail hosting.