When you pick a color you're picking it relative to one already on screen -- or something in your mind's eye. This color picker does not help solve either problem.
If you look at the paint chips in the store -- or the Pantone books -- you'll see they're organized a certain way. Often you pick the color and then you tweak the saturation and brightness. I do it all day every day. Even the dorkky CSS pre-processors have features for tweaking saturation and lightness. It's what artists do.
This tool makes a mess of saturation in particular.
Meanwhile nobody's demanding to do Delta-E crossfades on #ffffcc vs #ffccff in SASS. Hmm. I wonder why.
Color picking is often handled by swatches and fanning out real-world books of similar tones. Fiddling with a computer is great, and if you think it's important that your screensaver randomly pick cool colors -- hey, if this helps you, go for it.
You're likely far better off limiting the color cube a different way. Perhaps by popularity, or culture, or by simply typing in a couple dozen colors that don't look like shit and calling it done.
The swatches at the bottom of this Wikipedia article show the difference.
https://en.wikipedia.org/wiki/HSL_and_HSV
CIE* gets you more comparative, perceptive uniformity however when picking a color that's almost exactly what you don't care about.
Author would benefit from an art class and/or two hours reading the mind-numbing tech documentation around color theory.