I've added two elements to blindfolded rhythm changes. One, to do the same thing with my own composition, improvising on it until I can improvise on it successfully, and secondly, to do the same thing on "Don't Blame Me." The idea is not to get stale, and not to learn improvisation in only one key. At some point there will be a breakthrough, in which the improv in these other tunes will be as good as in rhythm changes.
On the classical front, I played one of the Mompou "Música callada" series for my teacher, and she said it was very good, in very specific ways that she could tell me. She is not one for empty praise so I knew that she meant it, and of course she still had suggestions. It feels very good to master a piece at this level. It is not difficult, but I couldn't have played any piece that well last fall.
I've thought about my goal on the piano as getting to 80%. But 80% of what? If I can be at 10% but play well, within that limit, then that is like being at 100%.