Italy is quite well served with Rome (Easyjet) Milan (Ryanair) and Pisa (Jet 2). Switzerland ....Geneva (Easyjet) Basle and Zurich would be useful though.
I would like to see Wizzair or similar serving Eastern Europe.
There is a gap in the shape of Austria with Vienna/Salzburg/Innsbruck.
Jet 2 757 a/c would be able to tackle the longer range routes on a loco basis, eg Greece/Turkey