[Snowflakian]

@synapse, the only real defense I have for those characters is Legacies and lasting impact on the world around them. It adds to the source material and also extends it to create new stories and characters that represent different kinds of people for others to relate to.

The same as changing races can help those races, more diverse aesthetics can help those that also share those features. Like hair color, eye color, or really anything that can cause some form of emotional attachment in the reader or viewer to continue on watching or reading.

That being said, there are areas where there is no defense. In particular parentage. If you've already established one character is caucasian, be sure any children or mothers line up to what's needed.

There's also problems in things like Avatar the Last airbender where race is key to the story itself. That's not to say Avatar messed that up. On the contrary it was the only thing it got right. -_-
They set up the earth nation as asian with a more chinese focus. Water nation was appropriately color shaded to be more offwhite ethnic of anything. Air nomads appeared more mixed like tibetan monks or european, and Fire nation was changed from asian/potential japanese to more towards a war driven india that worships fire.
Because of these 4 elements each representing a full on culture and race, they have to be seperate or explained appropriately to fit within confines of the defined world. So long as the changes make sense or fit with the desired story I'm whatever with it. Like Miles inheriting the mantle of the spider. He's part of the history now. The lasting impact of spider-man has turned into a legacy. Which is also why I like the children characters though, as it extends the legacy of other characters as well and their lasting impact on the world besides how it also gives more persona types for people to relate to or for others to look up to.
(For those curious, the bad part of avatar was the exposition, lackluster actions scenes, overtly condensed story especially on the only other highlight of season 1, and an utterly lackluster avatar state finale. Series could be salvaged for 2, but damn that was a weak start.)

I don't like the poof randomly so and so iconic hero is now this barring alt-universe stuff which is different or even reality bending mcguffin, but I do let that slide for background civilian characters who could all be frank sinatra lookalikes or elvis and I probably wouldn't care.