A version of The Tailor that could make decent reductions in size would be great. The Tailor is great for making morphs to turn breasts into watermelons, but try to use it to make smaller breasts, or flatten them for male characters, and it gets really jagged and icky. That alone would be an instant "Credit card is locked and ready to buy" program. The items that Netherworks and OpticalSingenoid listed would be great as well.