Hey Dr Larsen, check this out. Not all of the Japanese Infantry pieces from the Milton Bradley game were the darker shade of yellow. I recently got a lot of pieces from a seller on eBay which included a bunch of the original game pieces. I was surprised to find the Japanese Infantry were a very pale yellow, almost the same color as all the other Japanese units. See the pic below, the one on the right is the current infantry piece from the 1940 games, the center piece is from the MB game and is probably what you are more used to, as was I. The Left piece is one from this bunch that I just received yet it is ALSO from the MB game. I didn't know they came in this light a shade until now.
Interesting... you learn something new every day...
For me the key is simply having decent infantry in 1 other color for some sort of elite/SNLF unit. Since in the real world SNLF fighters were armed like and looked like IJA soldiers almost exactly (except for a slight difference in the shade of their uniform which is barely noticeable) a different sculpt isn't essential for me. Since I have plenty of Red AAP and olive WF infantry, I feel like I have this covered. Throw in the fact that both WF and TT give a decent tank upgrade with a Chi-Ha in about the right size, that leaves me with the position that the main thing I'd like to see for Japan is a fuller naval line-up. Since FMG seems committed to their program which includes only one of each naval type, and I haven't yet seen much interest from any of the other venders in an expanded naval piece set, I'm increasingly thinking I'll probably have to resort to buying and painting a bunch of Panzerschiffen to expand this side of the game...