I've done some research and am considering as well, though I might wait for the motorola phones to release. Have you encountered apps that didn't work? Like banking and stuff seems to break a lot of the time.
90% of apps work, no finagling required
Next 6% might need some fancy setups, like setting up storage scopes or other privacy settings so they can function as expected. I won't pretend they are always intuitive, but if you really can't figure it out, someone on the internet has already had the issue and posted their solution online
Another 3% are your banking and similar apps. Some work, but some are needy, and I have these in another profile which has the sandboxed Google play mirror and other Google services that GrapheneOS mocks
Then is your last 1% that are so stubborn that not only require Google play, but they have the audacity to require you be logged in to Google play or they won't start. Personally, I just refuse to use these apps when I get one, as they are random dumb ones, like some incredibly privacy invading videogame app. However I'm sure there will be some app you find that is like this. I guess you can log in, or heck make a third profile and hopefully don't need that app often. I guarantee there is a friendlier alternative that is worth looking into if you do feel you really need that service.