Airbus 215
If Baby would 'not want to tread on the toes' of bmi mainline at LHR by using LTN, wouldn't the same apply at LGW, after all, both are similar distances from LHR, one being north and one south. As for STN, with the harp opening routes there like this is no tomorrow, another Loco coming in there would find it pretty tough plus further easy expansion in the pipeline