Really, 12 presets isn't that many. I have so many characters that would be so great with presets, yet only allowing you to have 12 at a time really restricts that.
If Kovu ever gets back, I think the first update that should happen should allow us to more than 12 presets.
I think 50 would be a good number. Of course, most people won't really make 50 presets, but it would allow for much more room.
Of course, unlimited presets would be wonderful as well. Though I doubt that's possible.