Deciding the best ICO is actually not a single question, do you mean the best ICO from which you can get good ROI over the launch or very short term or your goal is to stay connected with the devs/project as a partner/investor over a long period of time.
In terms of delivery, allotment and project, I find "Kyber network" was one of the best ICO, in terms of real world problem solving Mavin Network is one which I consider is a great idea to make everyone an influencer to the promotion market.
If you are looking forward for upcoming ICOs which you want to invest in and can give you good returns, you have to look forward to the market sentiments, the team behind the project, the supporters, advisors, companies which support and back them up.
RPX (Red pulse Token) was a great example of how market sentiments affects/effects the success of an ICO.
If you can make your question more clear/precise, may be I can help you further!
Cheers!!