If you are a first time GrapheneOS user, dont make the switch too jarring.
Even if just use one profile with google services installed and all oyur old apps, your security and privacy is already much much better than using standard Android :-)
your level Security and Privacy you need is constantly shifting. With graphene as base you can change over time and adapt to your then current needs.
get rid of invasive not needed apps, move google services to another profile, you even have the ability to move back to the Pixel Android OS if you really need it.
This is what I value about Graphene: no compromise in terms of security, privacy and choice.
Now one of the only downsides but this is not something GrapheneOS can change, its googles doing: Apps that only run on certified Android install will not work as GrapheneOS. And Graphene most likely will never be Google certified. This also extends to using google pay with nfc.