At this point it’s really hard to predict. There are thousands of altcoins in the market and many more are emerging. In my opinion some potential altcoins would be ADA, BAT, ONT, IOTA and NEO. I think NEO is yet to show its potential and it requires almost no fees in transactions for NEO. Another altcoin is Binance coin (BNB) which is used in the Binance exchange. It’s been performing pretty good too.