There are a lot of potential coins and projects that could have potential in the coming future. My personal favourites are:
ETH (because of the adaptation of their Blockchain tech but it might be too late to get into that one)
IOTA (They have a lot of adaptation by big companies and organisations such as governments)
Cardano (there is an interested amount of chatter on with connection to their consensus algorithm)
Waves (might be worth holding in the long run with more adoptation)
Bitcoin Origin (seems to be a bit of excitement about the possibility of this project. Greener project, Proof of Ambassador algorithm, Sever-less Blockchain etc etc, [read through their whitepaper])

Keep on the look out for coins that interest you personally