Niknak
I also have been in and around aviation for many years too and happen to think that Manston is a little gem - waiting to be polished!
You say that Infratil have done a great job with Prestwick and yet take away Ryan Air and you have an airport very similair.
Of course along with a popular loco comes a lot of passengers and then along comes those magic franchises that you talk about.
You also fail to mention that as well landing fee's that there is a handling charge per pallet and fuel uploads, which generally amount to 100 tonnes per flight.(b747)
So in that respect, Manston isnt that far away.