When graphing an image or extracting unique color values from one in a color worksheet, things go a little slow if it’s not a small image. (Like, even a 1000x678 pixel image.) It’s not time to go get a cup of coffee, but I’m still inpatient. 
Also when sorting in color worksheet, for example by L*, when there’s 45,000 colors in the list.
Task manager shows when ColorThink is crunching those numbers, that it’s using 13% of the CPU. That’s Windows speak for using 100% of one of 8 logcal cores (a 4 core processor with hyperthreading), and that the program isn’t taking advantage of threads.
ColorThink’s speed would be much improved if it used multithreading, even if it only did so in the few cases where it would benefit from it - like working with images. Multithreading, of course, would not show a user-noticeable benefit everywhere, so no need to re-write everything using it everywhere.
Even better yet, would be to be able to give ColorThink a very large image like a 9626x6529 pixel image, and be able to do sampling rather than doing every pixel. (Even like 1 million pixels out of the 63 million there.)