CatchThePigeon - as I say, I've not done this as a "commute" but do a New York work week often enough that I'd say for a Monday-Friday set-up you would want:

- On the Monday, LHR to JFK departing around 5/6pm - allows a decent day of work in London, sleep an hour or so later in the flight, land JFK at 9pm and bed at hotel by 10pm (if you have Global Entry and a car waiting): means you get a few hours zzz even if you wake up at 3/4 am Eastern time; I would at a push depart London a bit earlier and get to my hotel in NYC around 7/8pm and then head out for a quick bite; I wouldn't depart London much later as that entails probably falling asleep more on the plane and by the time you get to bed on arrival your body will be waking you up within 2/3 hours

- On the Friday: the Friday morning daytime flight is optimal if you can manage it with work - get a day of work done, land LHR Friday evening and home by 8/9pm - you miss Friday night a bit but otherwise much better for jetlag; the second choice would be depart JFK on a c. 10/11pm flight on Thursday night - enough for a full day in NYC, get to sleep ASAP on board, then you land LHR mid-morning with a shorter day to get through before early night London on Friday