Could Wizz actually make a base at LTN currently? The benefit of the current operation means that the first wave of EZY flights have gone as the Wizz wave arrives so there's space to accommodate them. If Wizz were to open a significant base at LTN where would the planes sit as the airport is pretty full overnight.
In time perhaps, once the airport has grown, but for now the likely growth will surely be more of the same type of operation and the introduction of the A321 on key routes