if you want to degoogle the only way to run some apps without unprivileged code (GMS/microG) is to use grapheneos & its sandbox compatibility layer. this is unfortunately only available on the pixels.
I also worry you won’t be able to use some of the customization options that the nothing phone 2 offers with its hardware when using a custom ROM. if thats something u care about.
I have the pixel 7a & have had essentialy no issues with anything for what that’s worth.
common aegis W