I would focus on how active the dev team are, if they get things done according to the dates in a roadmap then you can bet that the team behind the project are actually people interested in the development of the project. They also need to be communicate with the audience, sometimes you find projects where people show interested but the team doesn't provide feedback.

A whitepaper is important, but nowadays, it seems like whitepapers mainly use buzzwords and use a lot of technical terms to make them sound smart to draw attention, and there's also the fact that some projects simply copy-paste a whitepaper from anothe project, so you gotta be careful if you're only look at a whitepaper to evaluate a project.