Thanks so much everyone for the encouragement and interest!
Greyscale, you and others have helped me work it out - the add-ons are needed to make an outfit of it (possibly the black and white contrast from yesterday made the basic more interesting on their own vs. today's dark denim).
However, to me a decent black top and jeans/pants will always "satisfice" (thanks MaryK for that useful term!) - when the layers come off, if a neighbour comes to the door unexpectedly, I still feel fine in the basic version. The black top will not show splashes of tomato sauce or wet marks from cleaning or whatever my daily routine inevitably (and literally!) throws at me. The layers are not needed to make it look 1/2 decent. The polish, at least, is still there with the black.
Anyways, I'll keep at it ... Greyscale, your capsule of shapes (vs. colors) has given me something to think about also ... my black top capsule at the moment has one t-shirt button-up, one crisp button-up, one long-sleeved crewneck, one long sleeved v-neck t, a fitted scoop neck (short sleeve) t, a more fluid scoop neck (short sleeved) t and a tank top. And a knit v-neck sweater. Imagine if that was all I needed! O Bliss!!