jimsam GrapheneOS is pretty great. But if you conceive of it as being the stock OS plus more security and privacy you may be disappointed, because you may well run into one or another feature of the stock OS that is missing, or which you need to install some app to get, or which works differently.
GrapheneOS is AOSP plus security and privacy and lots of features, including many features of Google's OS. Probably anybody running AOSP on a Pixel who switched to GrapheneOS would be deliriously happy. But that's not many people.
If you are genuinely willing to experiment, great! If there is some feature of the stock OS that you use 100 times a day and can't live without, maybe ask about that feature now. If something is not available now in GrapheneOS, don't expect that asking for it will make it happen soon, or maybe ever, even if it seems like it would be easy.
Effortless cloud backups are not available and probably won't be for a while. Backups of any kind are currently somewhat manual and not super-easy. For me personally that might be the head of the queue. But I am prepared to wait for that.
If there's anything you must have now, it is possible that need might force you to flash back to the stock OS.
Just my personal opinion, speaking for nobody else.