I'm not afraid about getting my server IP blacklisted, because there are several settings with the DNS records to avoid troubles like that.
But for my business emails, I'm using Zoho.com, because they offer 25 Mailbox with 5GB of storage for each one with your own domain for free. It's a good solution when you work in team.
For the smtp, I have used mailjet.com in the past, but there is nothing better than you own mail server with the required configuration to send emails without ending in the spam folder.