I don't connect through LHR being N.London based, but I agree with most of your LHR comments, I first started as a regular business traveller in the 80's and whilst the the flying bit in the middle has got exponentially better, the terminal bit at each end has gone ever downhill.
Apart from the odd book and maybe a bottle of water, retail interests be naught. I want to get through the airport, on the aircraft and away. I am doing a too regular trip LHR-Eindhoven at the moment, flight leaves at 08:00, my last queue to get through security was over an hour on Monday morning. What with car parking (£43 for 1.5 days), m'way delays, ATC delays, it is getting to be a real trial for what is a simple hop across the North Sea.
Before Christmas I drove to Eindhoven, via Harwich, went on to some meetings outside Brussels (killing another short hop trip..) and had the added bonus of doing a raid on the booze stores in Calais before coming back through the hole in the ground. The whole trip was more relaxed, controlled and managed in my own timescales than any air trip. I don't mind driving, the sea crossing on a fastcat was excellent and a GPS took away the navigation hassles.
Given all the other troubles at LHR recently, I would (and have on this board..) suggested folks avoid LHR for transit, if they have another option. It's a shame and maybe T5 will help, as well as Heathrow East (although the building I suspect will make the Central Area carnage for a good while) but with only two runways, LHR is going to be marginalised as a "world hub" in the next 10 years.