I think in the first place will stand Cardano, in second EOS, and in third not yet created at the moment cryptocurrency.
May be! I think! You can see Top 3 coins in 2020 on
https://coinmarketcap.com in top #10
the development of current coins will greatly affect the development and price of the coin in the future. so that with the current development of coins can know which coins are very capable to be reliable in the future. such as Cardano, Waves, and IOTA coins that become coins that have the high potential for development can be a good coin for future use.