Check the first 20 list and take your pick. My choices are ETH and XRP. I bet they will make a boom in the next 1 or 2 years. Also, if you are into cryptos and you like supporting new projects, my pick is BTCN. This coin has exellent, transparent idea with the upfront names behind the story. It reached CMC in a no time and already has a strong and extremely active community. As far as I know, it is already present on a couple of exchanges. It is quite appealing to me so far.