@Oly5 does the turnlock hobo feel huge when on your shoulder (as opposed to crossbody)? I’ve been eyeing them but worried about size, I’m quite short.
I have a Mulberry Ledbury (Bayswater shape but smaller, grab bag) and a beautiful putty coloured Birkin-ish bag from a little shop in Ibiza town that I have used every day for work for 3 years and still looks like new, but which is lined in suede and therefore exceptionally heavy.
I agree with the other comments - classic colours, leather, restrained hardware and details, no huge logos. A fairly classic shape will mean that you carry your expensive bag for years and it will go with all sorts of outfits.
I can see why the Longchamp Le Pliage are popular, they are incredibly practical. But they are a bit done to death. I have a cheap knock off from eBay, complete with leather straps and flap. It does the trick for when I’m travelling with work and don’t want to carry my heavy bag.