It's easy* to setup Hashicorp Vault with your own CA and do automated cert generation and rotation, if you are willing to integrate everything into Vault and install your root CA everywhere. (*not really harder than any other Vault setup, but yaknow). I may go down this route eventually since I don't think a device I don't control has ever accessed anything I selfhost, or ever will.

I have a wildcard subdomain pointing to my public IP, and forward port 80 to an LXC container with certbot. Port 80 appears closed outside the brief window when certbot is renewing certs. Inside my network I have my PiHole configured to return the local IP for each service.

Nothing exposed to the internet at all. There is a record of my hostnames on Let's Encrypt but not concerned if someone will, say, deduce apollo-idrac is the iDRAC service for a Dell rackmount server called apollo and the other Greek/Roman gods are VMs on it. Seemed like a house of cards that would never work reliably, but three odd years later I only have issues if a DNS resolver insists on bypassing my PiHole. And that DNS resolver is SystemD-ResolveD which should crawl back into whatever hellhole it came out of.