Hello, rohlfo
I think your idea is good. When it comes down to mid-game (4+ turns in) this card can pay off. I also think that it should be a permanent in the OTHERS theme, because the windmill itself is NOT air, it's a machine.
This card serves very well within the average range, making it a very subtle addition to the "others" group. Nothing over the top, which could make it fit nicely in the Air starter deck. I think that after Gnome Rider, Rustler, etc. that this card will be quite redundant, mainly because Air has enough Beatsticks as it is.
So more or less, I find this useless in higher levels, but there is nothing wrong with using this card in the lower levels.
Good luck to you!