Well, for me, the whole racial thing is a non-issue. I'm part Vietnamese, English, French , Irish, Cherokee, German, Polish, and probably a few others I haven't found out in my research (I'm a Historian), I guess that just makes me American. Oh, and my brother married an Italian. Guess that at least I'm diverse.
I mean if you really want to see one of every possible type of human, we're gonna need a bigger ship.
As for diversity, do you want the extras casting to have a quota? "Gee we need anther Hispanic, and an Asian, maybe an Eskimo...." For me it's good enough that they have at least a good mix and good actors, of course we can break the crew down even further, we got a Yankee, a good 'ole boy, a limy, a Korean, one black(don't know which tribe he's descended from though), and we could go on and on.
Of course we could knock out some aliens to make room for more ethnic groups from Earth, maybe Starfleet has an affirmative action policy....
The point is the show has a diverse cast and the stories are getting better.
And hey, maybe to Andorian eyes we ALL look pink....
"Retreat?! Hell, we just got here!", annonymous American Marine, WWI
"Gravity is a harsh mistress....", The Tick