The paired center seats are very nice for a couple.

Agree that they wouldn't be very comfortable with a stranger...

I do find the window seats narrow... I think the advantage BA have is that the club world seat "footprint" is rectangular, while the IB footprint is angled in towards the feet... As a result the BA seat gives the impression of more space (even though it might not have much, if any, more).

The new seat is much better than the old one in terms of going flat, entertainment, privacy... but you can certainly feel isolated / trapped in the new one.