Basically I'm at this point: 'what's the easiest self-contained box to run and maintain', with conditions 'I have an IP but it's not dedicated (ports 22/80/443 unavailable)' and 'there may not be existing DNS/SSL for this server but I can set it up' and 'SMTP from this IP is not desired/desirable, but I have an existing offsite ISP allowing relay with credentials'. This doesn't strike me as particularly weird, except that in the latter case Google is not an option (GFW'd from China).