I'm confused by your question.
I practiced groundscout because I felt like my ground dodging needed to be worked on. After I felt like I learned what I wanted to, I put AC back on my Scout and went my merry way.
confirmed.
I don't recall implying or stating that air scout isn't competitive at higher levels of play at any point. On the contrary, I think that airscout can be very competitive at higher levels of play. The extra degree of maneuverability is pretty significant. I know some good scout pilots can forego AC when pubbing, but I think that most of them would probably choose to equip AC if they were in for a serious fight. I could be wrong though.
refuted. But I don't know many who play scout in comp.
I don't know what you mean by your third question so please clarify that.
It was humor. Can disregard.
In summary: I think that AC can be useful when used well, can overexpose someone when used poorly, can certainly be competitive at higher levels, and should be a universal movement mechanic instead of an internal (though I don't care too strongly about that last point). I'm happy to elaborate on any other points.
Hawken is about bipedal mechs and bipedal mech combat. AC turns the game into air combat a few meters above the ground. I would WAY prefer that the air game be limited to a few classes only, and have serious tradeoffs. An example of the reverse: Scout is fast on the ground and slowest in the air. AC in its current implementation removes that restriction for most players: a crutch to rely upon when things get slightly difficult.
I don't think it should be universal, and I think it should require skill to overcome the adjunct shortcomings (which are missing, mostly, except for slot deprivation in the current game).