but, just personally, I would have liked to see that reiterated here, specifically, in these instructions, because I don't think it's entirely clear [...] It wouldn't have bothered me at all if you'd said something like: If the chromatic character you want fic for is not listed in the options choose 'Any' and say how much you'd like fic about any character, including any unlisted characters, just to let your Yuletide writer know that's an option.

But doesn't the sentence before that expressed this sentiment: Your writer is under no obligation to write the character you might mention in your optional details unless you have asked for them in the 'characters' slot.?

However, dark_agenda could edit the discussed sentence to If the chromatic character you want fic for is not listed in the options choose 'Any' and say how much you'd like fic focussed on that character in your request, and use a freeform tag like 'chromatic character'. Remember, however, to offer alternative character options from the ones that are listed. Or something along that line if that would help?