Perhaps it could be cheaper, but then last a limited number of turns?
That would be more along the line of what Zblader suggested with markers. Also, if air quanta is favoured over air creatures, then the energy back could be quanta of your mark. So, combining this, it could last 5 turns, cost 5, and give you 2 quanta of your mark each turn?
Then you have to feed it more air to create more? (can't really disappear, it's a windmill...:s)
Anyway, just thoughts, will give it more though, thanks for feedback