Bitcoin and Ethereum is the all time favorite and the best cryptocurrency I think. If you want to invest in any other alternate cryptocurrency, then you need to do your own analysis.
make own analysis be better than ask to somebody else find out information about tokens you want to buy and try to touch history to see the future find out every detail of information that you can collect and make a conclusion by buying a token.
I think the best cryptocurrency to invest are still Bitcoin and Ethereum because both crypto are already trusted by many investors that even it encounter a huge market price fluctuation but still can able to recover at soonest possible time.