The newest Pixels are the best given that's what Google will support the longest, and with every Pixel generation they make a lot of improvements.

https://calyxos.org/about/faq/device-support/#update-timefra...

Pixel 6 is right around the corner, however it'll take a few months for us to get it all going (getting the phone, porting Android 12, making changes for Pixel 6)