He isn't listed because he's a Civ Leader (he was actually taken out of Civ4's GG list).
That too is a decision I disagree with - Yamamoto wasn't the moving force behind the government, an honor that falls to a series of army officers culminating in Tojo. If you're going to write a list of period "great generals," Yamamoto's pretty much a must-have. However, since I lack the coding skills to do anything like this, that's worth about the paper it's written on.
Now, back to something more constructive...
Generals:
Alfred Travers Harris
Theodore Roosevelt Junior
George C. Marshall
Ernest King
Frank D. Merrill
Engineers:
Clarence Johnson
Frank Lloyd Wright
Prophets:
Alfred Rosenberg
Andrei Zhdanov
Nikolai Bukharin (A stretch, but the Purge didn't happen until 1937)
Pius XII
Spies:
Lavrenti Beria (Could also be a merchant or an engineer - he wound up in charge of a LOT of stuff, but his most famous accomplishments were at the NKVD)
Nikolai Yezhov
Genrikh Yagoda
Richard Sorge
Leopold Trepper (Controller of the original Red Orchestra network)
Ian Fleming (Average work as a spy, but leaving him out seems criminal)
I've bothered including a list of prophets as the people who spread the values-system of their given ideology. With the exception of Norman Rockwell, who would rightly be classed as a Great Artist, but so perfectly captures the "American Way of Life" that he could arguably be called a prophet of "Americanism," all of the ones I've listed have been people who argued loudly for a given ideology. Rockwell's arguments were on canvas, but were arguments nonetheless, which is why I added him.
The problem is that the generals during the war period really overshadowed everyone else, and it's easy to start getting into division-level or lower commanders, as I did in a couple cases (Truscott, Darby) on the list I added, based on whether their actions became textbook how-to cases. It's slightly harder to build a good list of scientists, because they're easy to pick from, but engineers especially get shortchanged, since, let's be honest, how many of us know off the tops of our heads the chief engineer behind, say, Taipei 101? I know I can't, and engineering's supposed to be my field of choice.
It would be easy to assemble at least a short list of cultural figures, but you're handling artists differently; it's actually a novel approach that requires considerably more work than throwing out names, and I'm intrigued by the idea of handling "great people" as "great works" instead. After all, there's nothing historically inevitable that says that Einstein had to be a scientist; he could have remained a patent clerk forever. Relativity, on the other hand, was going to be found.
A note on a few of the generals - A couple of the generals I've listed either spent the war in staff positions (Marshall, King) but were enormously influential on the military policy of their side, or never rose higher than equivalent to assistant division CG, but developed rather heroic reputations in those posts (Darby, TR Jr.). Also, a correction - Galland served in JG 26, danger of posting before looking up references.