East Campus accommodation is modern and nice, but also expensive! Though it is close to Law so you can roll out of bed for lectures (especially Goodricke).
The accommodation on West campus is mostly 60s brutalist architecture, definitely not old Oxford vibes! Some like James college and 'new Vanbrugh' is newer (and nicer)
The option that sounds like it ticks all your boxes is actually Fairfax (Vanbrugh)...
It's about a 10 min walk from west campus, but I live there and also have some lectures in the law building and getting there by bus in the morning is quite reasonable as east campus classes start at 9.30 instead of 9.
Fairfax is a pretty 1920s townhouse so has that history, It is also catered accommodation. The main downside for me is you're not split into 'flats' and the kitchens are quite small so you don't get that same flat bond. On the flip side, if you don't like the people in your kitchen, you don't have to see them, and theres 89 other people in the building you can choose to be friends with. Breakfast and dinner are a good time to socialise, I've gotten to know a lot of people by 'table hopping' (sitting with different people each time). Obviously the people living there change every year, so I can't guarantee anything, but everyone in my cohort is lovely!