Adam- What would be your cut-off age for such no kids flights. The problem with that plan is not only would it upset people, it would not totally be effective in eliminating annoying kids on flights. Allow me to elaborate: I am a firmly beleive that with kids the more they fly the better the behavior. Therefore, its totally possible to have a well travelled 4 year old who understands his/her expectations better than a 10 year old who is taking his first flight. An alternative is too have status only flights, which would eliminate some adults but also kids who dont fly enough to behave well, in any class.
I am not advocating either plan, rather pointing out that having status only flights is probably more acceptable than no kid flights.