It's samey to an extent but then every brand is.
But it's not hard to mix a plain cardi from White Stuff with an edgier dress from French Connection or Ted Baker, or All Saints- as an example.
I do understand your problem because I feel there is little choice in the low-medium price range for women aged 40+.
Brands like Reiss and Whistles are ok but mainly manmade fabrics and I wouldn't pay £200ish for an everyday dress.
Have you thought about Hobbs, LK Bennett, Phase 8 , Jigsaw, Kaliko etc?
These are mainstream and mid-high end but not designer prices, and then there are other brands like Warehouse, oasis, Banana republic, etc where you can pick up some pieces very cheaply.
Depends on your style and work needs. I need casual for 80% of the time and rarely wear dresses, so find it easier to mix and match across brands without having a 'look'.