So what did you eventually conclude? - something like:
Freestyle/synchro length=nominal length+1" ??
Dance length=nominal length ??
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I think if you look at a search engine for
Kids colors
You will find that kids are most frequently associated with pure (e.g., saturated red, yellow, green, yellow, blue, violet) primary colors.
A lot of teenagers too.
I was once told that a general design principle is that as people become more mature, they move to less pure neutral earth tone (brownish orange, brownish green, brown, gray) colors, and off-white.
The people telling me laughed at me for creating false-color maps for image processing that had very distinctive pure colors. The implication was that, like Peter Pan, I never grew up.
They found my pure, distinctive color maps almost painful to look upon, and made me move to less pure, less distinctive colors.
(OTOH, I created a fiery mostly pure red/orange/yellow/white false color scheme for pictures from an orbital solar observatory that appealed to those customers - but they wanted those images to stand out and be noticed, and maybe to remind one of the heat of the sun.)
It is also possible that neutral colors, like off-white, blend without much notice with whatever a room already has.
Don't know if that is useful to you.