Here is an incomplete list of aftermarket distributions, also known as custom firmware or custom ROM of the original Android operating system by Google.
I am sorry but this list is... not-good.
Includes problematic ROMs (Copperhead OS), dead projects (AOKP), and OEM closed-source ROMs (MIUI)
To anyone out there, my personal recommendation would be: if you own a Google Pixel, go for GrapheneOS or CalyxOS, if you do not have a Pixel phone, try LineageOS and derivates (I am personally running crDroid with microG instead of gapps)
Yeah, the issue with banking isn't the OS / ROM per se but Google's trust model. I'd have to dig up the specifics but basically banks are hit and miss with any degoogled solution.
Yeah, I've just flashed it yesterday. It's amazing. You can keep most Pixel smarts while yeeting all the ad and tracking stuff. All my apps are working perfectly too unlike microG.