I actually started this list on Thursday, but my browser was naughty and I lost it. I'm just now getting back to it, and starting with Angie's suggestions.

• Waist-length, long-sleeve cardigans in black, white, gray, and various colors. These are essential wearing over short-sleeve anything in summer at work.
• Flat neutral shoes, in black, white, and rose gold metallic or blush. I have quite a few; this is whittled down to what I know I will keep. I'm shopping for navy ones as well.
• Black and gray boots. The gray have really made a lot of outfits come together this year by virtue of not being black.
• Skirts in black, white, and navy. I have more than what is in Finds, and I wear them all. All lengths in winter, knee or midi in summer.
• Leggings in black or navy. The NAS Spanx faux leather ones have seen a lot of wear this winter. I have fleece-lined navy that I also wear frequently, though rarely for work.
• Skorts in summer. I live in these when not at work or church. I want to upgrade to less gear-ish shorts, but it will depend very much on what size I am and what's available.
• Dark patterned/sheer tights. Angie may banish these to the "basics" category, but I would argue that they're an essential in cool weather. I don't like only black on my legs, so I now have 4-5 options in the gray/black family, plus a dark floral with burgundy and green that's a lot more subtle than it sounds.
• Jeggings. My AE X-Long hi-rise leggings from 2015, which are made no more. But they bring together a lot of casual outfits.