Sounds fair to me. Art is art. Everyone has their reasons for making art, and since artists don't typically see big bucks until after they're dead, I don't see why time and hard work shouldn't see some coin.
This was a really good story, my favorite of yours so far; and the models were very well done. I'd definitely pay to see Helga get even bigger (perhaps some sort of device malfunction), but I'd also pay to see whatever you come up with. Sometimes bribing an artist's inspiration is worth more than the art-at-hand.
Good luck
[descends back into lurker-land]