Wow. I’ve only just started testing it against GP, but it’s really slick and works really well. Lots more fine control than GP, and the only thing that isn’t quite as good is the photo editing on the app and web site, and that is on the roadmap. Oh, and I can’t see how to set up TLS but I might just be missing something.
My wife and I use Immich via Tailscale to avoid the need of any proxying and serious account management. That said, I have yet to fully transition from GP because I have at least one shared album that a few dozen people regularly access. Still need to test setting up a shared album w/ reverse proxy for this one. But then if I want to share another album I’d likely need to set up another proxy…or see if shared albums share a common URL I could use as a catch all. Still need to test.