Personaly I don't think anybody needs to comply with the typical chapter colors. I have seen a bunch of winning grand tournament armies that have custom paint jobs that have nothing to do with the colors listed in the fluff. I think of the origonal color schemes as a place to start if you have no origonal ideas. I have a blue scale based swordwind army. Another blue based high elf army, and a red and grey grey knight / Imperial gaurd army and none of them match the codex colors all that well.