I get it, there are significant advantages to playing those races as a villager, but it just doen't feel right to have so many... Under no cercumstances is it overpowered, but I think there should be some disadvantage associated with at least the flying class villagers (so taking cloud giant into consideration as well). Maybe like... They lose detect invis... Something that wouldn't really hurt their combat performance, but would mess with them anyways. I think something like that would at least make it go from a no-brainer: "Hmm, I've gotta make a rager... I know! Arial or Cloud giant." to a more thought provoking decision.
For svirf it just seems to me that they shouldn't be able to use stoneskin as a rager. It just "feels" too magical. I mean think about it. If you were a bloodthirsty pack of warriors bent on killing everyone and everything magical you could think of, then one of your pack of savages's skin turns to stone and they're all " Nah, its cool. Its my racial ability." I feel like the pack would immediatly cut that guy's head off. Also, stoneskin is magical in every other form known to Thera, so how can it just be completely cool for villagers? Flying for villagers I can understand: Arials have wings, cloud giants are born that way. But Svirfs have to invoke it.
I hope this didn't come off as a rant. I actually don't think villagers are overpowered, nor do I think these racial abilities are overpowered either. This is just my personal opinion on the subject. Just too many arial, svirf, cloud ragers around these days.