Anyone else here using FSPassengersX? It's a great addon, not too expensive. It allows you build up a career/airline, as well as adding in flight service, co-pilot actions, etc. Also adds in customisable failure rates.
I was just flying from Hong Kong to Osaka in a Cathay 777-200, had an engine failure about 1 hour in, had to declare an emergency after failing to get the engine to start again and land in Taiwan. Certainly adds a bit of variation. Another time, we blew a tire landing and had to evacuate the aircraft on the runway.