Ok, here are mine, starting at the lower price end and moving up:
H&M but only if you have the time and patience to rummage for the occasional rapidly disappearing gem. I have to say I've pretty much given up but I still mourn it. It's easier if you have a branch that stocks the premium ranges.
Uniqlo - I've had a few stinkers but it's about the best quality I know for the price range. Normally a good choice of colours. I wear it, my son wears it, my mum wore it in her 90s. I like the collaborations best, especially the Christophe Lemaire U line. Ines de la Fressange has a range out next week.
Cos?? The website's an absolute shocker but, if you have a local branch and time to try on, some of it can look surprisingly great and quality is normally good.
Hush - I gave up on them cos of poor quality but they have a lot of fans on here and it can look really nice.
Baukjen - I rarely end up buying for some reason but always look and often like. People who buy it seem to rate the quality.
Whistles - another one I've given up on because of poor quality for high prices. But I still like the look of it - modern but wearable.
Toast??? Another very marmite one. I avoid the dresses but love the trousers - best high street quality I know. Good sales.
& Other Stories - big sister to H&M. Not bought myself but some of it looks nice, not sure about quality.
Arket - an even bigger sister to H&M and Cos. Not bought myself but people on here seem to rate it.
Me and Em - not bought for a few years but when I did it was great quality. Again it's mostly modern but wearable although some of it is a bit up itself I think. Very good sales.
I'm also a big second hand shopper. But it takes time - which I didn't have until recently.