Figure I'd ask here, but I'm looking to set something up for email in the future, I'm looking into custom domains so that if something happens with one email account, then I have more security in mind to pick up from there as opposed to being screwed.
I know that fully self hosting email full stop is usually not recommended, so I'm up for any advice anyone has on that end.
If you don't want to fully host it yourself (which I think it's wise), then it's a good solution.
If privacy is important to you, ProtonMail has a good reputation, but I haven't been keeping up with the latest developments in the area (there might be other providers that suit your needs / budget).
I recently bit the bullet and bought in to mxrouting’s lifetime account. 10GB, unlimited domains, unlimited accounts, “forever” (for the remainder of the time mxrouting exists) for the semi decent price of $100.
I would go selfhosted and use a mai-in-a-box solution. Easy to setup, handles all the spam DNS settings etc and if you put it on an ip segment that is generally spammer-free, then you should have a fantastic solution (I habe used it myself for many years).