I don't know if the New Cross branch trains are heavily used in the peak, but it may be worth for those locals to use that service instead of crowding already packed trains at New Cross Gate during the morning peak?
I've used the trains from New Cross during the morning rush on the odd occasion. They generally leave New Cross fairly empty, with maybe 20% of the seats occupied. However, they then fill up significantly at Surrey Quays, for whose residents they must be a god-send, because they have virtually no chance anymore of boarding the trains from Crystal Palace/West Croydon.
Things at Surrey Quays may actually get worse when the extension to Clapham Junction opens, and that may lead to more people trying to get on our trains. This is because there are currently 2 trains at about 8:20 and 8:35 that arrive at Surrey Quays empty (straight from the depot) to help reduce the general overcrowding on the other trains. But those slots are actually 2 of the 4 slots per hour that will start at Clapham Junction from 9th Dec - so the chances are those too will be rammed full when they arrive at Surrey Quays in the very near future.
As others have said, the ELL is a victim of its own success. It's been a brilliant addition to the area, and bizarrely, getting a train to London Bridge now is usually a relatively pleasant experience. I cannot actually believe how we all managed on the 6-8 trains an hour we had before. However, it needs to be expanded up to 8 carriages not 5 and/or it needs to run more frequently, and it needs to run later into the evenings (the Olympics was brilliant for the later trains). And whoever designed a 4 carriage platform at Canada Water (admittedly 10 years before the ELL) needs to hang their heads in shame!