Yeah feel like mostly recently MIUI has become unbelievably bloated with random BS. Nowadays everytime I get a new xiaomi phone I start by unlocking the bootloader.

Yeah I switched from 99 % of Google services (the 1 % is google services used by my school etc. and youtube, for which I use NewPipe), however Google services should not be required for the likes of gmail or youtube, google services might be required for some games (google play games dependencies) or to receive certain push notifications (firebase notification service or something like that). When I used lineageos with MicroG (opensource Google Services replacement), my phone had longer battery life, but that might have been a coincidence.

Am using Elixir on my Xiaomi phone, I really like the customization stuff. It would be ideal if it would come in a variant without Google services :/ Otherwise it runs pretty nice.