Not quite sure why anyone would fly from the UK to New York via the Middle East, but that doesn’t seem to stop people suggesting it’s a good idea!
Business on BA is OK but recently one thing they have done that has wound me up is their ‘upgrade’ to the entertainment system. Previously (and still on some flights) there was Video On Demand system which basically meant you could start to watch any film at anytime rather than having to wait for the loop to restart.
The AVOD system is the upgrade, however BA have some planes where this system can’t be retrofitted due to the wiring system installed. One of the plus points with BA is that in long haul business you are guaranteed a fully-flat bed, but in some cases that might still come with an in-seat entertainment system whose screen is smaller than the one on your smartphone. Flying to JFK you should generally be OK though as it tends to avoid the really bad aircraft…
London City to JFK is interesting if you want to be different – and is the only BA route with on-board Internet access – but the lounge setup at the London end is nowhere near as good as at Heathrow.