Correct me if I'm wrong, but I think that the original diplomacy board game, and most of its subsequent US/Canadian editions have used the following color palette:
England -> Dark (Navy) Blue,
France -> Light/Royal Blue,
Germany -> Black,
Austria -> Red,
Italy -> Green,
Russia -> White,
Turkey -> Yellow.

I think it was an older British (or some other international) edition of the game that first substituted pink for England and purple for Russia. I'm not too sure exactly why, but perhaps it was for practical manufacturing or aesthetic issues (avoiding two shades of blue or white as a "color"). I think this alternative palette is probably the second most common/influential. Clearly, this website has followed the practice of using pink and purple, and I would assume that brown was substituted for black to avoid contrast issues with the overlaying black text and border lines. I think it was a prudent choice to use the alternative color palette and the desaturated tones do look very nice.

Anyway, my questions were:
Has anyone seen any other color palettes in the published editions of this game? I believe I've seen some international sets with different palettes.
Does anyone have any alternative suggestions that they prefer? Does anyone here assign the colors differently when playing over a physical board?

I have two physical editions of the board game: the 90's US Avalon Hill/Hasbro version with metal pieces, and a 60's Canadian Games Research version with the traditional wooden pieces and the physical (contour-line) map. Both use the "original" palette (navy/blue/red/green/black/white/yellow).
The French blue of the older set has faded into more of a turquoise, and that has led me to think of an alternative color scheme given these pieces:
Navy Blue for France, "Turquoise" (faded light blue) for Turkey, Yellow for Russia, White for England, and the rest the same.