Full respect to you T2
Flying instruction needs many more people like yourself, many of the GA instructors I've come across are in instruction for various reasons that have little to do with service, vocation or dedication which is one of the reasons standards are low.
Personally I do not think you can be a rounded senior instructor without a background in airline or RAF flying and that's nothing to do with the size of the aircraft, its to do with the professionalism and discipline and the constant goal of finding better and safer ways of doing things. Multi crew flying from both seats also gives you a much wider experience of managing people, which is a valuable skill in instruction.