If you want to do a London-originating daytrip from either LTN or LGW to Madrid, look at Easyjet.
To fly London-Madrid takes about 2h30. To have a flight departing Madrid at 7 am AND a flight departing London at 7 am requires 2 planes. Ryanair have chosen to have MAD-based airframes + crews as a competitive spoiler to prevent Easyjet, Vueling and Clickair being able to make too much cash out of Madrid - it's certainly not Ryanair's most profitable base.
Similiar thing applies to the Malta-Trapani route. The premium routes from Malta to Sicily will be to Palermo and Catania. Trapani is 70 miles by road from Palermo - it's a leisure-focussed airport, not a business one. A route like London-Rome seems far more likely to do profitable day-trips than Malta-Trapani.