FINALLY!
Now, let's check 'em kits. Both blue and red sets are identical except for the color, so my comments will apply to both:
1) Esc and horizontal ("ANSI") Enter are present in black and yellow; vertical ("ISO") and numpad Enter keys are present only in black. It's fine if you leave this as-is, but consider adding accent versions of the latter Enter keys.
2) Consider including the F13 key.
3) ISO is correctly supported in base. You don't have to change anything, but do consider replacing the R4 \| key with R4 <> (to follow the "terminal style" instead of the "PC style"). This change would apply to the Nishi sets as well.
4) Consider adding an 1.25U R4 Fn key.
5) Nishi sets are missing the R3 1.0 \|む keys (it IS correctly present on all other rows, though).
6) Same goes for the pure Hiragana sets: the R3 1.0 む keys are missing.
7) The 2.25U and 2.75U space bars in the base kit: EXCELLENT. Now, could we ask for an additional, separate kit with just those four keys (red and blue, 2.25U and 2.75U)?
Looking forward to this!