The way I see it, the interiors were in black-and-white so doing figures or statues in the style of the comic books but with the different-colored bandanas is a good compromise. I was also always an advocate for interchangeable heads on the NECA figures. Even with Raphael they could have given him a brighter, more-cartooney shade of red as an alternate.
I absolutely understand that they initially all wore the red but at the same time we all need to understand that there's maybe 1% of the population that was introduced to them in that way. Even when I was a kid and I learned about the all-red bandanas it was a curiosity, a footnote, an obscure piece of trivia before they got their "real" colors.
I also don't see the uniform red as the kind of thing that Eastman and Laird would have refused to change if asked. It's pretty inconsequential and I doubt it ever factored into the stories themselves (I could be wrong) and if you could travel back in time and say "hey guys, maybe they'd be easier to tell apart if they had different colors, don't you think?" they might have even done it themselves.
But yeah, again, the whole thing can be solved by making interchangeable heads. Something that simple would render the entire issue a non-issue.
