What color did you use as your base color for the armor plates? I used scorched brown/brown ink was as a base then lightened it up with thin layers of graveyard till I got it where I want it (Changed my mind after a test model and went for a different scheme in th end thou
, I liked the look and it got pretty close to the codex, but i decided to steer clear of codex colors in the end)
I think with tau armor schemes the color really reflex's the environment they are in, the only constant for color for the different septs is each septs markings', which are orange on Sa Çea.The colors in the codex for this septs armor even says that this color is used by all septs for urban camo.
So you could paint them whatever color you wanted along as you include some orange sept markings.
Im not a big fan of following codex schemes so as far as Im concerned do what you think looks good then come up with a good reason for the color difference for all those fluff sticklers