ZB & TOM based at Luton
The question was asked a few posts ago why both airlines have relatively few aircraft based at Luton.
Parking would certainly be one of a number of issues should either airline wish to increase numbers now although it wasn't that long ago that Monarch only based three airframes at Luton during the summer.
The lack of IT operations out of Luton (and Stansted for that matter) goes back a number of years when all of the major tour operators took a decision to concentrate their London operations out of Gatwick. Comensurate reductions then took place to the Luton operation so that in the main, only the really popular destinations are served now.
Luton had the benefit for an additional period of all IT flights to Cyprus as thy were not allowed by the Cypriot Government to operate out of Gatwick (and I think Stansted) but this restriction ceased in the run up to Cyprus joining the EU.