+1 to everything you just said - I’ve been using Immich for a little less (370 days, thanks to the same button). It’s feature rich and rock solid.
Only thing I hope they add to the mobile app is the Years/Months/Days option, to make it easy to quickly group, then find, your photos. It’s the one thing that keeps me using my phone’s own Photos app (locally - no cloud sync).
The casting bit is the missing piece for me.
I’ve built a RasPi with Kodi for our caravan, to use Plex and stream our free-to-air TV here in Australia (using Musk’s space innernets). I just miss being able to cast from my phone, for the occasional thing I can’t do with a Kodi add-on.