These figures are much easier to make out than the masters. The artist tends to sculpt (at least partly) after being inspired by the works of Don Troiani. Troiani has a print called "Cemetery Hill" showing the meeting of Generals Doubleday, Hancock, and Howard on the evening of July 1, 1863. On the scan of the figures:
Doubleday is #2 from the left, top row
Hancock is #4 from the left, top row
Howard is #2 from the left, bottom row
Also figure #5, top row appears to be Custer and #5, bottom row wears his hat much like "Little Phil" Sheridan.
Just trying to make a few educated guesses - I beleive a lot of these figures could suffice for mounted officers on either side of the conflict.
My guesses too. Is that "Unconditional Grant" bottom row 4th from left! I wish we had him in the famous picture leaning against the tree, but I'm going to really enjoy these sets anyway when we get all 4 Staff sets, plus some Infantries, Cavalries, some Artilleries ... :-)