I just realized I didn't specify that I was talking about Hubbard's CTIs, when I was talking about essentials.
I agree about the Airto's and Farrell's as being solid albums, too. Turrentine's Sugar and Cherry are worthwhile sessions, as well.
I'm sure I'm leaving out some others, but since this thread was specifically about Freddie's CTI albums, that's what I was responding to.