It would be a cool app, and allot of new techniques may be invented or discovered while developing it. But one should ask what are the attractiveness criteria? what do you mean by "Data-driven". The data comes from other users? I mean aesthetics norms comes from society or the user, or both?! Very subjective! if we build tools to enforce aesthetics norms on users from the "common sense" - (things that never made sense too me), we are basically killing all the peculiar beauties in the world, say, a cute pimple next to the lip.