At some point though, someone is going to call a halt to the growth in GA traffic surely as pax flights seem to be the only game in town
Depends on what you define as 'GA'. If it's light aircraft i.e. Cherokees, Cessna 152s, etc., well Luton sees virtually none apart from the handful occasionally operated by the Britannia Airways' Flying Club and by Eagle Flight Training.
The former is understood to be under close scrutiny by the new management at TUI (not just the LTN-based Club but also its operations at Redhill, Wellesbourne and Liverpool) on the basis that it's being subsidised by the parent airlines.
The latter may soon be subjected to some severe operating restrictions on its training flights which having a lower priority than 'normal' flights, are likely to be the subject of a blanket ban at certain times during each day, because of other traffic.
As for 'GA' in the guise of corporate aircraft, this is a real moneyspinner for LTN's operator (as opposed to LTN's owner Luton Borough Council which - unlike for scheduled and charter passengers - receives nothing for each Corporate passenger).
So it's highly unlikely that corporate movements will be discouraged although at some point in the not-too-distant future, these flights will probably be 'co-ordinated' for runway slots as is practice at Gatwick, Heathrow and Stansted (currently, they are not co-ordinated at LTN).
As has been mentioned numerous times before, the 'naff' roads are going to be improved, with a dual carriageway planned right up to the airport from junction 10.
It's rumoured that the Department for Transport has withdrawn its funding proposals for this road improvement and if true, unless Abertis is allowed to build it and then run it as a toll road (cf. the M6 Toll) I doubt that this grand plan will ever come to fruition as the local Borough and County councils are not exactly the most dynamic or proactive when it comes to local road improvements.
As for the airspace, seeing how long it took for Terminal 5 to get through public scrutiny and then receive approval, and judging by the CAA's track record, seems probable that you're actually being optimistic!
