Gender and Race in Kidlit

I've been thinking about gender and race in kidlit. I was reading another blog about the lack of diverse race in some genres (notably sci fi, apparently) and thinking about my own writing. Another blogger posted about race in writing, and about having the courage, if you are "white," to write about other races and possibly screw it up, but do it anyway.
I was thinking about my own writing and how I may be (inadvertantly) contributing to the problem. What I'm saying is that none of my major human characters is anything but white. This does not stem from a desire to have a "white" world, at all. This stems from my deep fear that if I tried to put minority characters in my stories, that they would wind up "white" with dark skin. And that I will be blamed for getting it wrong. Is this enough excuse? Should I do it anyway? I am not interested in writing books about race. But even if the book is about pffffffff..... say, eggbeaters, why can't some of the characters be other races besides white? Well, they are, but only minor characters. I'm still thinking about this.

To be honest, part of the problem that the majority of characters being "white" seems to be the distribution of authors. No one complains that Toni Morrison and Alice Walker write almost entirely using African American characters. And duh, why should they? It seem to me, the world needs more writers that aren't white. Yes, yes, the rest of us should also try to reflect the races of the world more accurately, but some of us are chicken. I feel like the pressure to do that perfectly if I do it at all is more than I can cope with.

But what about gender in picture books? Is male still the 'unmarked' gender? I realise that my default setting for anthropomorphic characters is male. So male equals neuter? Something like that. But this won't change unless we allow some of our characters to be marked for a while, until there is enough of a mix for long enough that it becomes normal.

Hmmmm... This post has come out a bit jumbled. I am going to have to think about this a bit more...