This seems reasonable to me. They were nice enough to make the game free in the first place, and not have to pay for extra worlds. They even gave us a crapload of options to customize our character without creating presets, which were also free. Wanting to add your preset into the game is something extra you want to add to your game, so it makes sense to have to pay for extra stuff that does not exactly affect your gameplay. Presets are just a little something extra that give your game a bit more visual and artistic freedom.
Plus, it's only three or four bucks, guys! Whether it is a one time payment or a monthly/yearly payment, it is still a good deal! When you buy games in stores nine times out of ten the game itself costs thirty to fifty bucks, and then to add expansions that costs another twenty bucks. If you think of it this way, the game is already free, and your just paying for an expansion, and three/four bucks compared to twenty is great in my opinion.
Just thought I'd give my two cents on the matter