My biggest complaint about perceptual colour spaces has been that they make working with colours near gamut boundaries really
hard.I agree, this can be awkward. I like using perceptual spaces because they are self-evidently a “neater” starting point for colour work than something artificially distorted like HSL or (horror!) RGB, but it’s important to recognise that they offer an incremental improvement and don’t magically solve all problems. In particular, producing a useful and/or aesthetically pleasing result still isn’t necessarily as simple as varying one axis in isolation, because you can quickly fall outside the available gamut that way.
As a practical example of this, I recently needed a scheme for a variation of syntax highlighting in a structured document. My requirements were:
1. around 10 clearly distinct hues
2. all colours maintaining good contrast with a white background
3. no colour appearing too bright relative to the near-black unhighlighted text
4. all colours at a similar level of perceived lightness to avoid unintentional bias or emphasis.
My starting point was to choose evenly spaced hues within a perceptually uniform colour space, pick a medium-to-low value and look for maximum chroma in each case. This wasn’t a bad start, but it still needed significant practical adjustments like increasing the value for colours around the yellow/green area and dropping a hue entirely so I could space others around the blue/purple area more widely. Otherwise, however perceptually uniform the scheme might theoretically have been, in practice it would have ended up with the yellow/green area colours looking washed out and the blue/purple ones not distinctive enough under some realistic viewing conditions.