I know its not a big deal, but walking backwards is the same speed as if you were walking forward, now in most games walking backwards is slower, just saying it would seem probably better.
Certainly helps people backpedalling away from your Tank's Jet Gun and your Assassin's RB lunges. Stops Supports from keeping you in Heal/Hurt Gun range while you can't hit them back either. Sounds like a good idea. Jetpacking can still have the same speed though, gives some sort of advantage to backpedalling for particular classes.