Skipness One Echo
You are obviously as entitled to your opinion on the merits of SEN being a true London airport as anyone who believes the contrary, but I think a couple of your reasons are dubious and comparisons with Manston and Oxford will raise more than a few eyebrows I feel.
SEN is on the shore of the Thames Estuary and not "on the coast" in the usually accepted sense. It's position relative to water is irrelevant surely.
The EDI route has not worked for the very reason that has been stated, in that a double-daily is the minimum requirement to attract the business traveller and at the time of writing this has not been tried.
I don't have any verifiable figures to support this, but anecdotal evidence suggests that SEN attracts users from a much wider catchment than would at first sight be expected. Yes, it is largely outbound traffic at present but that is likely to change and the over reliance on leisure traffic will also reduce as a consequence.
I agree that it will take time for SEN to become a natural choice for the majority of London-based passengers but it is still early days and ads such as those aired recently on London radio stations will help.
Can we not all applaud the complete transformation that SEN has achieved in just two years and wait and see how it evolves over the next couple of years? I'm not sure than many people would have predicted it would have a throughput of one million pax annually at this stage, but it does.