It is better for an ICO to have an MVP or even a working product that is already used by somebody as a service or a product. The target audience should not only be ready to pay but paying already. The tokenomics - how the token will be used within the ecosystem makes sense. Even if all those things are in place the team should worth trust and be ready to implement the project to a point of time when it will be used by big audience enough for you as an investor to make profit.

I would suggest you not to invest right now into ICO due to  current market situation. The ROI in ETH is not quite well even for projects with their own blockchains. The situation may change any time. Lets keep track on what is going in the industry.