Do some research about the project, check whitepaper, roadmap, and website.
The roadmap and the other detail you mentioned is not sufficient enough in my opinion mate. Some project have a very nice roadmap and wp but stillcturns out to be a bad prroject in the end. Theres realy no way we can avoid joining a bad project so best way is to join each and everyone of them like airdrops so that you wont miss the opportunity of getting all tokens.