What about all the helicopters in the game sitting engines running burning fuel going nowhere?
And speaking of helicopters, how about standing on the main rotor, and not getting thrown to the ground?
And of course, the rotor blades passing through you? They should have generated knockback.
Pretty much the same for vehicles, they just drove through you. They should have generated KB, too.
And in the Vanguard base at the firing range, when a toon wanders in front of the targets the shooters should stop firing. There should be an announcement, "Cease fire, clear the range!"