I don’t think the intention is to look like Kate Middleton when she was newly engaged though, you can be minimal and on trend.
perhaps replace the Breton for a thick cotton boxy t shirt, replace the kitten heels for something more practical (suede trainers? Can’t remember if they had trainers), the cigarette trousers for carrot fit ones… The dress is not for me at all but at least slightly more modern.
ObvIously thats just one opinion. I could never have a capsule wardrobe though, I adore clothes and especially interesting cuts and prints!