Ellington: "And His Mother Called Him Bill", "Far East Suite", "Afro-Bossa", "Piano In The Foreground", "Such Sweet Thunder", "Suite Thursday", "Dance Concerts-California 1958-Volume 6". All are superior to the titles mentioned above. The first four are available on vinyl, albeit expensively. "Piano..." is a trio record.
Basie: "E=MC2" (sometimes known as The Atomic Basie), "Chairman of The Board", "Basie Plays Hefti", "Kansas City Suite". The first two are available on high end vinyl. Again, these are stronger titles than those listed above.
If you don't require modern sound, Ellington's "The Blanton-Webster Band", "Fargo 1940", and "The Complete 1936-1940 Small Group Recordings", along with Basie's "The Complete Decca Recordings", are jazz essentials. The Ellington small group set comes from Mosaic, the invaluable reissue outfit. Good listening!