"They are all workhorses that get worn regularly, but are more like a steady, reliable backdrop for my favorites or serve a specific function that my lifestyle requires. Purging them would leave a hole in my closet, but I'd have no trouble finding a replacement that would work just as well."
I wish I had such confidence in finding workhorse replacements! As a petite with fussy feet, this can be quite a struggle. Most of what I consider "favorites" are the workhorses. To others they may appear boring and functional, but I know just how long it took me to find exactly the right item that fits, flatters, and is comfortable and natural and easy to wear, in a quality fabrication that will stand the test of time and result in great cost/wear. I don't like futzing with my clothes. I don't like scratchy fabrics, tight waistbands, and stiff fabrics. I want structure -- but structure that is comfortable to wear.
These ARE the exact pieces I'd grab if there was a fire! Frankly, I'd leave the starring role, dramatic pieces behind. I love these pieces too, but they are on trend today and may not be next year. Emotionally, these play a critical role in my closet (mood dresser) but emotionally, I know my whims change with the trends, so I could part with these. But not the favorite, supporting-act workhorses, the clothes I could not get dressed without.