To me 700s are too austere.
First class with the tables are ok.
But theres no culture or features to a 700, just bland, hard seats.
maybe in a few years if a few bits get rattly and loose they may liven up a bit.
In asia, stock like this would have video advertising screens, news etc full length of the train... only thing like it in the UK was the now scrapped HEX units.
The 4:3 screens on the 700s (the smaller ones on the left) are apparently capable of playing video. But as anyone who saw the graphics and audio recordings for engineering work (one voiced by Geoff Marshall) and the glitching (often causing all screens to fail and require a reset), it soon became apparent that the software wasn't up to the job of even a static image + audio file, let alone video.
If the DfT thought it could make money from advertising, there's no reason they couldn't change the software to include all the information on the wider screen and keep the smaller one for ads - but I bet most people would sooner see live train info being shown, as against TfL info (useful as that is, what about other train services and details of connections at main stations etc?).
The wide aisles were to speed boarding and alighting so that the trains could deliver very short dwell times in the core section. It's called a design compromise.
The 700s are absolute lifesavers during busy periods, which isn't necessarily so much about commuting now, but things like moving people from events, or even when a train is cancelled and you have to squeeze more people on.
They work brilliantly for this, and had the aisles been narrower I am sure a lot of the benefits would have been removed.
Ultimately, they have fewer seats and that may not be ideal during commutes (but many commutes won't be that long distance, and people can accept standing especially if they'll be on their bum all day anyway) and off-peak there's plenty of space and probably nobody trying to sit next to you (unless you're in a group).
As an aside, I think the approach taken by Greater Anglia with open gangways and 3+2 seating is extremely odd by comparison.