- Team: their experiences and references
- Idea: whether it has mass adoption appeal
- Source code: does it have a working prototype
- Financing: is the hard cap too high or reasonable
- Marketing: is it over or under-marketed
- Community: does it have enough support
- Hype: is it under or over hyped
You can also watch YouTube videos whether others review them to help formulate your opinion.
Look at other websites for ratings such as icodrops, icobench, icorating etc.