I self-hosted for a long time but I eventually switched to fastmail mostly because, no matter how much I tweaked, I couldn’t get the spam down to a tolerable level and I got sick of tweaking the weighting on the various filters in spamassassin.
Thanks :)
I use https://mailinabox.email which handles everything you just mentioned.
Any "sane defaults, regular updates, impossible to shoot yourself in the foot" package to recommend?