There's lots of smaller VPS and VM providers -- even local IT companies. Mythic Beasts and Bytemark have been good for me.
If you want to use Linode for your CPU time and disk, probably there are providers for outbound SMTP that you pay a small amount for to use as a smarthost.
If you want to use Linode for your CPU time and disk, probably there are providers for outbound SMTP that you pay a small amount for to use as a smarthost.