On the subject of this Aerowalker thing I have just a few things to say that should keep everyone happy: They probably exist. Maybe only as prototypes or for very specific missions, but they probably exist. They wouldn't very common of course, but if V. has a story in mind he wants to put them in then I think that should be ok. So they hypothetically exist as a weapon, but aren't used much in favor of more specialised vehicles.
But for those of you who are arguing about there usefulness I give you: The Enomeg! They may be EPIC, but they could easily be replaced by a special division of Veteran SpecOps. Because that's what they are: SpecOps +1. So just consider how much money and effort Xarkon is wasting with the Enomeg Program, when actually the same thing could be done easily with minimal effort. Compared to that, what's a few Aerowalkers? Besides, Yavakaro definitely has enough money and technology to throw at a project like this.
I doubt there would be a prototype based around a completely unworkable concept. It'd be similar to General Motors unveiling their new square wheeled car project.
Enomegs are proven in combat, based around a relatively simple (and likewise proven) concept - that of enhancing the body and mind through a rigorous training and technological improvement. Like you said, they work as a force multiplier. These 'aerowalkers' as you have dubbed them fill a role already covered better by existing weapons systems.
Most of all, it goes against the majority of Scorp's existing 'rules' regarding walkers.
Anyway, my question is regarding the Wrognoth. Have you made a decision regarding their inclusion in the universe? I would like to include one in the story I am writing, but don't want to do so if it's premature or not decided.