What are the upcoming cryptocurrency ICO's with greatest potential?
None. ICOs are made to take the money out of uneducated investors.
There are few ICOs that have potential but I won't tell you and you should never listen any ICO recommendation.
When someone tells you to invest, it's already too late.
But they may have to know some ico, for their research to recognize which ICO they must follow, but they must be careful in choosing several ICOs, because there are some ICOs that eventually become fraudulent. I suggest they have to be more careful in investing using ico.