Graphene is was simpler to set up than any other ROM I tried before it. Never felt the need to change back to stock android and it's been over a year for me.

Biggest thing is just know what you need to back up beforehand (2FA codes, pictures, etc) and make sure you're ok with losing some of the cool pixel features like call screening. I do miss that feature still. Can't use GPay for NFC payment at checkout (not a problem if you normally have your debit/credit card on you already).

Other than that, you can get pretty close to your normal pixel experience with a better baseline level of security and privacy. Don't let the puritans scare you into not using things like Google play services. If you need stuff on your phone to make life easier, just use it. Privacy is a spectrum, not a hard set of rules!