in my opinion, at the moment, Nuls, Cardano and Icon could potentially be the best.
Pro nuls. This is the third generation technology of the blockchain and the people only pay attention to it. Global blockchain project! May offer the possibility of using smart contracts, the mechanism of subchains and interchain consensus! It will be hot in my opinion!
ADA cryptocurrency is one of the most discussed cryptocurrencies lately, and as you already know, the value of digital money is growing in direct proportion to the growth of its popularity among traders and investors. Due to this, Cardano's cryptocurrency managed to quickly break into the TOP 5 of the most capitalized blockchain projects.
The goal of the Icon (ICX) project is to unite all blockchains worldwide. Simply put, now every project is working on the selected blockchain, whether it is Etherium, NEO, Bitcoin ... whatever. Within the framework of their own networks, each company can operate according to its own rules, and this does not interfere with networking. I think ICON is a worthy candidate to consider as a supplement to the investment portfolio.
Thanks for attention!