I don't really have set outfits tbh, and I do change my mind every couple of months. At the moment my wardrobe has got: grey skirt suit black skirt suit grey trews and black trews a couple more jackets in various fabrics/styles 3 pencil skirts 3 short skirts 3 full skirts a load of plain black tops a couple of silk printed tops a couple of cotton printed tops 2 white shirts 4 dresses I have other stuff, but these are the things I think I'm most likely to be wearing over the next couple of months, I think.
I think set outfits (if you mean you only wear one top half with one bottom half rather than mixing and matching) makes your wardrobe very difficult and inevitably huge.
I have quite a casual wardrobe, so the foundation is 4 pairs of jeans (cream, grey, denim - all skinnies - plus denim boyfriends), half a dozen tops (shirts and tshirts), a couple of jumpers, a couple of work dresses (I only need to be formal for work a couple of times a month) and a couple of casual dresses, one blazer (could do with another). Plus various boots/shoes/sneakers/sandals, a couple of different coats and jackets, accessories etc.
But the crucial bit is really that everything goes with everything else, in terms of both colour and style, so it all mixes and matches endlessly.
Hmm. I think I need to do a Remus on it and make a list of what I wear. I tend to love say, a particular skirt with a particular jacket and wear them together all the time. Habit I suppose. At least I have a basic palette of grey navy but of pinks and blues. Theoretically I could do more mix and match. See, I told you - I could do better I probably could do with a couple more skirts. Shoes, I have a plenty. Tops, quite a few. Lacking in bottoms (tho irl I have -physically- bottom a plenty )