The problem I had, when I tried to de-megacorp my e-mail, was with knowing whether the e-mails I sent got reliably delivered.
I set up SPF, DKIM, DMARC, used an IP not on any blacklists, and so on - everything guides told me I ought to do. Still, not only would my test messages often go to spam, I'm pretty sure I saw some vanish entirely, not even making it to the spam folder.
And this is a very insidious problem - did I e-mail X and they just didn't deign to reply? Or did my message never reach them?
I wish there was a 1-step process for white-listing known good emails, for a single address, or a single domain, or a list of either.
I also wish there was a process for exporting/importing these lists.
With SPF/DKIM/DMARC (whichever of those verifies that the email header was actually set by someone who has access to that email sending address) on and open-relay on STMP turned off, I envision a web-of-trust-lite world (which is probably the wheel I'm reinventing) where I and everyone I exchange email-address-trust-cards like business cards help to crowdsource what is and is not spam based on shared whitelists and degree-of-separation weighting. If I think something is spam, my 1st degree of separation (who has handshaked with me to verify that yes we've met) also probably does, but his colleague, maybe not.
MUAs and online email service providers would check the compiled whitelist for each account before running their own spam filtering.
We have good online adblock lists, can we do the same for email spamlists without 27 clicks to whitelist or blacklist emails?
Servers would have to not blackhole spam-tripping emails and reply with 'you spam = bad', that is another problem entirely.
I set up SPF, DKIM, DMARC, used an IP not on any blacklists, and so on - everything guides told me I ought to do. Still, not only would my test messages often go to spam, I'm pretty sure I saw some vanish entirely, not even making it to the spam folder.
And this is a very insidious problem - did I e-mail X and they just didn't deign to reply? Or did my message never reach them?