Very eloquent young man - point well made.
But the other side of the argument was also interesting.
"A longer runway would allow larger, yet quieter and more efficient aircraft, to use the airport."
True or False I wonder? Flybe use Dash-8's into Norwich, which are amazingly quiet - even on the climbout. I've been riding past Norwich airport before now, and a 4-seat Cessna made much more noise taking off than the 17:30 to Edinburgh that followed it.
Local infrastructure is a good argument though. What are the road/rail connections like? Stansted is brilliant for transport interactions - as good as Gatwick; nearby motorway, and railway station inside the terminal complex. Norwich is quite hard to get to - esp by public transport. How is it at Southend?