Do I win?
And then came kamigawaWhite certainly isn't just good, nor is Black evil, though they arguably fall under those alignments more often than the other colors do.
But let's back up a bit. In a way, I find white aligned somewhat more scarier than black. Because while black is more focused on the individual, white's more focused on the group. That also means while black's good at killing individuals, white's more suited for killing, well, everyone.
Take the blue-black person you mentioned. A person who is all about power (although that's mostly black). Still, that person can be somewhat reasoned with. You can make deals, although the deals will most likely be in their favor.
A white-aligned person wouldn't. You couldn't argue with them or convince them. Especially a white-blue. That's the very definition of 'control'. In other words, that nature would lead to things that instead of killing you, completely control you, whether you like it or not.
To simplify even further, black is 'I will do this, regardless of the cost' selfishness.
White-Blue would be 'You cannot do this, no matter how much you struggle' control