Is it possible yet to change the visibility of old posts? The absence of small privacy features like this—features that FB does have—always was very off-putting for me. When Google+ was launched they made a huge deal out of Circles, but it strikes me that since then Google has pushed Google+ more as an alternative to Twitter than as an alternative to Facebook (and I don't like Twitter much).
Anyway, I used Google+ so little that I deleted my account in a petty rage when they shut down Google Reader. It's actually nice to have one less social network to worry about.