a control tower that is now a gymnasium and a few roads near by with aeronautical names.
You forgot the Hatfield Police Station and the KFC outlet in the Grade 3 Listed DeHavilland office buildings.
...the aircraft would receive more direct and intensive attention than they ever did whilst in RAF service,
Having spent long periods in both RAF and civilian maintenance I can assure you that no civilian aircraft receives more direct and intensive attention than an aircraft in RAF service.
For evidence of what happens when a group of enthusiasts try to restore an ex-RAF aircraft to flight and maintain it in that condition, look no further than TVOC. Apart from trained and highly skilled labour, it takes lots & lots of money and spare parts to fly a complex military jet aircraft. From where would your prospective civilian E/E Lightning operator secure the revenue to stay in business?