I like the Chronogical Classics I have, the bad thing being that they overlap with the King Jazz material I have in three other forms! I totally dig the Jazzology releases of the older stuff, Jazz Record Story, Trios and Quartets, Apex Blues. . . .The Delmarks are also great.
I ran across some lps that are out of print that are really nice solo piano on Euphoria; one has Hodes doing "Watermelon Man" and I love it! I'm a big Hodes fan. . . I still have some more to get but I'm slowly doing so, because I don't want to be at the end one day, and I am savoring them slowly. . . .