This makes me angry:
I run my own mail server in a VPS. Its IP address is NOT blacklisted, and I have both SPF and DKIM properly configured. I do NOT send bulk mail.
But still, Gmail classifies my personal emails as SPAM.
Same email with same exactly same contents, sent through PoBox SMTP server goes to INBOX. Directly from VPS, goes to SPAM. No explanations, no public blacklist. It looks like they just don't want people going "indie". Sigh.