Wouldn't it be a good feature if you could reduce the clarity or sharpness on colours individually? I'm thinking a good colour for that feature would be orange for skin. But other colours might be useful too.
There are two powerfull tools that cam be aded to the lightroom pannels.
The HSL pannel has color and point color control. What if you can build a new pannel next to the brush pannel that has all the adjustments(wb, exposure, clarity, sharpnes,...etc) BUT has the point color technology, so you can afect a single color with these setings, ex. the skin softness may be eassily adjusted in a bunch of photos at a time rather than painting one by one.(the portraiture plug-in does that decently)
The other thing that might be added in the detail pannel is a highpass filter with it being the last effet added on export.(capture nx2 has it as a filter)