I have a couple domains that are very low volume for outgoing mail. I use Migadu. I’m happy with their cheapest tier ($19/year for both domains). They have catch-alls and many other nice features.
Edit: They have no hard limits on the number of addresses, users, or domains and such. They just want you to be reasonable. You choose a tier based on your average quantity of outgoing mails per day. Again, there are no hard limits; they won’t cut you off unless you abuse the system.
I’ve been running tiny tiny rss (aka ttrss) on a vps for well over 10 years. It’s been rock solid through many upgrades. It’s got a great web interface & android app. There’s a decent sized community for it. The only drawback is that primary dev (fox) does not tolerate (what he conciders) dumb questions. The new docker compose deployment is brain-dead simple.
Sheet music carved in stone