i was just poking around (nice site C:), and saw this thread, and well, I want to make a suggestion that could solve the preset problems of taking up server space, and users being able to see other's presets.
Since FH uses ogre, you could use Flash in conjunction with Hikari library to render the textures onto each character. With this method, you can have the user upload their textures onto some image hosting site or somewhere on the internet, and feed the image URLs into the game, where the user's client, on request, will download the textures from the urls provided. It's the method I use for my own game. That way, you don't have presets eating away at server space, and presets are visible to everyone. I have code and an example (again, my game xD) that shows that this method actually works. c: I don't know if using Flash is exactly uhh... memory efficient, but it might be worth a shot.
I hope my explanation wasn't too confusing :'D