I think the text based nature of the site is a challenge you need to overcome - Why would I want to read any of these descriptions? A few thoughts for solutions:

- Let people upload cover art: This will let people who have decent design chops/family in the business/etc. Stand out a little more. And as Amanda Hocking's books show the cover can be a stock image with a genre appropriate font well within the means of anyone with PowerPoint.

- "This + That" pitches: I know some VCs and Hollywood types love this format e.g. Alien is "Jaws in Space". What if you could pull in a couple images from Amazon to illustrate that this pitch is for a book that is sort of like "Game of Thrones" meets Robert Ludlum.

- Author photos: let the authors make connections with the sponsors. Let them tell their stories "I'm a stay at home mom who has been dreaming about this book for a decade"

- Rewards: Galley copies if it gets published, Buy the "For:" in the front, etc.