According to my mole, further and future large scale expansion at Coventry seems unlikely since a renewed interest being shown by TUI at Luton. Remember, the UK HQ of TUI is located just beyond the perimeter fence since their relocation from north London a short while ago.
TUI were anxious to distance themselves finally from the planning issues at Coventry, by selling the control of that airport recently.
The lack of different airlines commencing scheduled services from Coventry means that with East Midlands, Birmingham and Luton in proximity, it does not have the sophisticated transport infrastructure required from an airport. The independent bus from the city centre is hardly an 'on-site' railway station?
Coventry will have a future, once it gets competion from another airline. Too many eggs in one basket, if Thomson decided to pull out, what then?