For once I actually agree pretty much with SOE.
Expressflight, your arguments only help prove the point that SEN covers a fairly local catchment area. Due to your location, it's no wonder you see SEN as a breeze to use. There's by no means anything wrong with that, it's people in your shoes helping SEN to prosper.
However you completely fail to recognise the bigger picture. It's a competitive market out there with 5 much bigger rivals. SEN is always likely to struggle to serve London in the proportions that LHR, LGW, STN, LTN and LCY are. SEN has indeed done very well and hats off to them. But they are only going to ever be a small regional airport on the outskirts of London which it's local catchment and only a handful of people travelling to/from London are likely to use and value very much.
Further afield it becomes much less attractive, regardless of its service level. For example, around Coventry and Leicester where I am, LTN, STN and even LGW are all regularly used. I guarantee you that SEN probably wouldn't even come close to consideration, that's if it's even known as a commercial passenger airport!
Around Coventry in particular you even see National Express Coaches and Airport Taxis all the time with ads and prices for transfers to LTN, STN and LGW airports, but never SEN. You must surely see the point!?