Why does easyJet IOM LGW need to use a bus to get to the arrivals? It is domestic? When I fly on easyJet domestics like BFS LGW, the a/c normally goes to passenger walkway usually one of the 55's at the North.
London City is fast and convenient as an airport but getting to central London is a slow journey stopping everywhere.. I don't find it pleasurable and typically the price is steep for the flight, though in the example that you have cited is competitive. All that said I don't fly IOM London, so my good experience is on using LGW ex Ireland, or UK domestics and it is in my opinion all round value for money and quick to central London.... Clearly your experience overall is different.