A tricky balance between worthy and recognition
Putting Rosalind Franklin on as a kind of consolation prize smacks of white male guilt and would have probably just annoyed her.
Put Maxwell on but most folk would not have a clue who he is sadly.
I would say that Stephen Hawking and Alan Turing get enough publicity maybe.
(Go to Bletchley Park BTW. Excellent place).
I'd like to see Lovelace and Babbage on a fifty.
Having a pic of the Engine between them on the note would look good and delight the anti-counterfit folk.
Maye Sydney Padua could draw them ;-)