I still think you can't have it both ways. Either colourblind casting is universal (with occasional exceptions, eg Martin Luther King) or it isn't. In the case of Ghost in the Shell, there isn't an overwhelming case to make the character any particular racial type, regardless of whether the casting of a Japanese American would have been nice for all the reasons you describe.

I do agree the live action remake was poor, and I much prefer the anime original (though I love Scarlett Johansson, who is great in many other films).