By contrast Wimbledon seems to have a lot of pinch points, and Stratford is just plain confusing unless you really know your way round.
Wimbledon is awful. Only one narrow set of stairs from each pair of platforms, and huge numbers interchanging between SWR, Tube, tram and Thameslink. Fences have been put up to protect the fast line platforms 6 and 7, but these have to be opened specially during Wimbledon fortnight and on Sundays when trains are scheduled to call - intending passengers being coralled until the previous train has passed.
On platfom 5 (the Waterloo-bound platform) big crowds build up near the stairs as seasoned commuters know that the only chance of getting on a train in the peak hour is to be near the last carriage, as passengers alighting at Wimbledon choose that carriage in order to be first in the queue for the stairs. A second footbridge, at the London end, would solve that but neither SWT nor SWR have ever shown any interest in doing so, instead building fences on platforms 5 and 8 that are meant to channel passengers from the bridge further down the platform but in practice mean they have to walk further to catch their train - on platform 5 they just double back to be near the rear of the next Waterloo train - on platform 8, the extra distance can mean missing the train, with a a delay of 30 minutes as most destinations served by that platform only have 2tph. (And of course people who have missed trains spend longer on the platform, adding to the congestion)
The number of people switching from NR ticket to Oyster (for Tube, tram or local Thameslink services) makes it a hotspot for fare cheating (e.g buy a ticket from say Woking to West Byfleet, carrying on to Wimbledon and then Oyster from there, so revenue protection squads often blitz the place, but this makes matters worse as they barricade the top of the stairs, ensuring massive and dangerous congestion on the platforms as people jostle to try to catch their connecting trains. I have more than once missed a (six minute) Thameslink connection thanks to that.
I also really don’t like Blackfriars, I’d rather change at Elephant & Castle which is saying something!
Blackfriars has one of the best views of any station in the country.