Perhaps a naive question, but I had always assumed that an A320 movement generates considerably more revenue for the airport than the average private jet. Is this generally correct ?
Not putting all your eggs in one basket comes to mind. There is an infinite capacity inside the CTA, the terminal and car parks. Biz jets leave these areas alone. Also using the pond as an example 4 Airbus stands can park 20 plus business jets during the day.
A new apron could be built on the eastern side of the short term car park after the second multistory is built but the real issue will always be the size of the terminal which would be hard to add further capacity to.