altcoin is the best altcoin that has a very good team in the back and the availability of con is very limited and has a very good development plan, otherwise it will be difficult to determine the altcoin is good or not, i will give coin what is good but this does not guarantee that the coin is good because I am only speculation of the above 3 factors (coin availability, team, and development plan) is the RAiBlocks coin (XRP).
https://coinmarketcap.com/currencies/raiblocks/