Absolutely agree with Chestnut and Mr Toad. I'm going to C&W again for DC2 (am 34 weeks).
FWIW, I'm American, so I get where you're coming from, although DS was my first baby so had no US experience of maternity care to compare to.
What you described sounds fairly normal for antenatal care at C&W and other London hospitals. Apart from missing a UTI, which is not good, certainly. I met about 8 or 9 MWs in my first pg, none of whom I saw during labour. Part and parcel of style of care here. Some were better than others, I agree.
If you were put off by hospital tour (and I admit I was) go look at another. I also toured St Georges and found they were much of muchness. You will find peeling paint in many hospitals, I suspect.
I had a bathroom to myself in the labour unit and was attached to pool room, as well. Unfortunately, I ended up with a EMCS due to placental abruption. The staff couldn't have been better during the whole experience.
Post-natal wards are unpleasant, they just are. But, hopefully you won't be there very long. With a CS I was there for 3 days. Not great, but hey ho. I have heard the same reports from mums at other London hospitals, so not sure what you will find elsewhere.
Remember, C&W (and Georges, maybe Thomas's?) are teaching hospitals and have many experts in the field. If things go tits up, that's where you want to be, en-suite bathrooms or not.
Also, I can heartily recommend a doula if you want continuity of care during labour. It made a huge difference to both my DH and I and I am having same doula again. Good luck with your choice, I know that it is an uncertain time and hard to face the unknown!