This is, almost verbatim, my exact same experience. Used pi-hole as an excuse to get a Raspberry Pi. Used it for a long time but got tired of troubleshooting. Discovered NextDNS (from this site), and have been a happy customer since. NextDNS has not been perfect (it looks like they abandoned their app(s)), but it has the added benefit of working outside of my home network.
Regarding the client apps, I find them to be mostly not neccessary now that you can identify clients to DNS-over-TLS and DNS-over-HTTPS endpoints. What do you miss?
Being able to disable it on the fly is the number one thing I miss the most. Additionally, it would be nice to interface through the app instead of the website, but that's definitely under nice-to-have; the website is functional on a mobile device.
