Reduce the probability of strange heads in random costumes

[temnix]

I don't mind those special heads popping up every so often in combinations the costume generator serves me, but they appear much too frequently. It feels like every fifth character is from the Kingdom of Eagles or the Cranium Collective. (Here is an idea for a supergroup: all members have to have brains for heads.) I think I know why: they are treated as a category of equal weight together with Normal Heads, Hoods and the others. But how many comic book characters sport heads like that? And whenever a monster head or a sphere appears above the collar, it rules out every other detail there - no face, no expression, no cybernetic lines, no glowing eyes... Push them into the back row.