Hi,
Thanks for the suggestion, I don't entirely see the value in it though, I mean surely the colour of the chars is already visible just by looking at the map + the compressor has the ability to reset the colour(s) of any char that is not actually using it's assigned colour(s).
Also I think it would only be (theoretically) useful for some of the display modes and colouring methods, ie. in the bitmap modes each char has multiple native colours (2 in hi-res, 3 in multi-colour).
It would be a lot of work and I will need some convincing.