I'd really like for light usage to be free, but I'm undecided as to the best monetization strategy.
One option is for model creators to be paid when users download their public models.
One option is for model creators to be paid when users download their public models.
It's not even clear if this is more risky than a paid model, because the internet landscape is littered with corpses of paid-model web applications which didn't take off "enough".