Paintings can come in low, medium, and high chroma. But, there doesn't seem to be a way to naturally boost colors without overblowing colors within Krita. Vibrancy is essentially boosting chroma/saturation in chroma mid-mask. For painting purpose, this would mean that a fine control over vibrancy requires you to manipulate chroma/saturation over Chroma L and M mask while subtracting with Chroma H mask and LL mask or just Chroma M mask. This would increase control over low colors painting. HSL curves can also work or even LCH curves if possible.

Any thoughts?

Edit, removing vibrancy means desatuating using Chroma H mask and M mask whilr discarding Chroma L mask or just Chroma M mask. This would lower vibrancy of colors without affecting low vibrance colors.