Seljuk, i believe easyjet are not currently in Tunisia due to an open skies agreement. However this is due to be abolished soon, next year i think? Apparently the Tunisian Authorities are a little relentless on allowing the likes of easyjet and Ryanair access as they feel it could damage Tunisair.
With routes from Gatwick, i personally would like to see more routes into Scandinavia, and im sure Stockholm is just a mater of time. With regards to OTP, With Aer Lingus recently announcing the route, perhaps easy will give it another shot just to over saturate the market.