What do think about ICOs like vDice, Janus and Wings DAO?
Still thinking about those three. I really don't like trading much and don't like to support PoW-based projects (obsolescence of that Proof-of type), so I'm taking part in a few projects and...
and which existing projects will do well in the coming years?
...the greatest bounding factor is not having enough time to deep-analyse. Too many details for me to make such prediction. I play with educated guesses. Look at community, look at dev's goals (raise money or raise awareness), and u'll get basic idea