To be clear.
If you change <COLOR ID="0" MainBackground="2242390" Background="4612266" Foreground="15724527" Numbers="15527148"/> to a new MainBackgroud then it will only look different.
But if you change a unit's Colour ID number from "0" to "10" not only will it look different, the "Support Scope" for the formation the unit is in may mean, the cooperation level between this unit and a unit from another formation may change as well.
There is only one principle of war and that's this.
Hit the other fellow, as quickly as you can, as hard as you can, where it hurts him most, when he ain't lookin'.