lings that could jump DOWN walls wouldnt be particularly overpowered, although going up would most definently render choke points usless against them.
Although lings do the most dps, for there price, they also have an extreemly hitpoint value, and can get slaughtered by any kind of splash.
It might also be interesting if they lept rather than ran.
It would be interesting if units like Zerglings and Reapers, could infact become flying units, for a short time, essentially taking to the air, and being targeted as an arial unit...
I mean zerglings would be the ultimate arial swarm XD
They would really have to nerf how it would look though (they would have to swarm like carriers) and limit the number of lings that can be locked on a single target