The old Flight was an absolutely horrid representation of actual flight, it was more like SwiftSwim in the air (actually that's exactly what it was) than flying. It had 0 connection to Airbending, and by that I mean nothing signifying any air being bent, no control on behalf of the airbenders to slow down, glide or do anything other than move. The new Flight might prevent you from fighting as well as you could previously, however Flight previously allowed completely domination of the air, comparable to the an airbending Luftwaffe. This new Flight is much more balanced, yet still allows the same (one might even argue more) mobility than the previous.