FLYAIR10
Interesting post, but I fear that the proximity of Ostend to Eurotunnel and many different vehicle ferry routes make flying to the UK ( or indeed UK visitors flying to Belgium) a rather unfavourable option.
For example, you can put 4 people into a car, and get a 5 day return on Eurotunnel for around £ 120.00 (€ 140.00) - so around £ 30 / € 35 per person. OK, so there's fuel to pay for, but provided you are fully tanked in Belgium (preferably with diesel!) you can avoid the higher fuel prices here. I really cannot see any airline, least of all Ryanair who dabbled in Ostend a few years ago, offering inclusive return fares (that is inclusive of all their rip-off add ons) anywhere near those levels.
I was in Ostend only a couple of weeks ago (by car) and clearly you have in OST, a very much under-utilised passenger facility, but a thriving cargo operation and I really cannot see much potential improvement in the PAX side, other than possibly grabbing a bigger share of the IT charter market to sunshine destinations.
I think that Manston in UK suffers from similar problems - proximity to Channel ports, and frankly a pretty small local market.