Ah, I get ya.

I've come to believe that, when it comes to RPF, there are 4 personae per character:

- the real one (that no one outside of the RL!person will ever get to meet. I'm referring to family, close friends and co-workers)

- the public one (while performing onstage, on TV, in a movie, an interview, a concert, etc.)

- the fandom one (where the fandom will cull all of the public data--interviews, TV/movie appearances, etc.--and create the RPF profile)

- the fanon one (which mostly describes signatures quirks and lines the RPF character is known for.)

To me, a good fic will play with the three personae (not the real one for obvious reasons).

Like you, I like RPF AUs that gives us enough of the 'characters' to recognize them but don't go overboard with the signature quirks/lines.