I think the most important usually: Famous Developers in Team, Interesting Idea, Apha version of project.This is the most reason why people invest on ICOs, there are some that includes the supply to be distributed in Bounty programs but these three is the most important.Though I am not looking this in an ICO but in a bounty campaign. The key to the ICO project is its team and project philosophy.Only the team is strong and the idea has a future, then the capital and management will be easy to solve.