Best Miles Davis Mono LPs to Start a Collection

My wife has had, I think, some sort of a mid-life crisis, a female version of male menopause, I suppose, and has suddenly turned into a complete jazz freak. It's all about jazz with her, now. And, God, in this new universe of hers, is Miles Davis. Although she has CDs of his, she has nothing on vinyl. (And why should she? I'm the one with the turntable.) Since I don't, currently, own a CD player, I would like to give her a collection of some of his albums. But, there are several parameters the collection needs to meet.
They must all be in mono. They should, together, comprise a retrospective of his many styles and groupings over the time period commencing in 1949 and ending, well, ending whenever they stopped issuing mono releases. You tell me. Lastly, they must all be, relatively, affordable. (The emphasis being on the "relatively", as I'm aware that these things don't come cheap.) Perhaps, there are some good sounding, more affordable reissues out there, for instance, or releases whose prices havn't been driven up by collectors.
I've already got some, though. These are:
1) The Miles Davis Tad Dameron Quintet in Paris International of Jazz may, 1949: Columbia AL-38804
2) Bags' Groove: Prestige 71095
3) Milestones Columbia CL-1193
4) Porgy and Bess: Columbia CL-1274
5) Sketches of Spain: Columbia CL-1480
6) Miles Davis: United Artists UAS 9952
All, of course, are mono.
So, what should I get, next?