I am sixty, but I like to keep fairly up to date, and think my style is quite contemporary (for my age). I find the following good quality
Brora - lovely cashmere. I also like their clothing, have quite a few dresses, tops and skirts. Usually buy in the sale as prices £££
Hobbs - some of it is nice. I find they are good for skirts and trousers, some dresses. They do use a lot of polyester though, but also have lovely 100% wool skirts.
Baukjen - B Corporation and most of their stuff is made in Europe. I stay clear of the fussy dresses, but they had the occasional nice piece.
ME&EM - lovely quality, but lots of polyester (albeit recycled). Again, usually buy in the sale, but if I see something I love would snap it up as they seem to do quite small runs.
Russell and Bromley - I usually buy my boot and loafers there. They are mainly made in Italy and Spain. Can pick up good bargains in sale.
Didrikson - can't beat their coats IMO. I am currently wearing a long parka which is waterproof, and a puffer type long coat which is fab. I have lots of other coats but tend to wear the Didrikson.
I also get the odd thing from Whistles, Jigsaw, Seasalt, M&S, John Lewis and Toast.
For lingerie I mainly buy Fantasie and or Panache. Both brands fit me nicely, wash well, and last for ages. I almost always get at least 20% off from somewhere.
Someone mentioned Johnston's of Elgin up thread. I've never bought knitwear, but their gloves and scarves are fabulous. I've been wearing my cashmere gloves for quite a few years now and they are toasty. I bought a pair from TKMaxx this year, thinking they would be as warm, but they are not.