Nice art works and slick experience. Some suggestions

1. While waiting for the art to be generated, get the user to do a hot-or-not between some existing art to get a better sense of what they like and then generate them something

2. Have a little more feedback on how much longer they'll need to wait while generating

3. Once generated, show the artwork framed and hanging somewhere not just the rendering

4. When a user kicks off a job, kick off a bunch in parallel using some other styles in case the style they pick really doesn't work well.