The best cryptocurrency to invest is bitcoin because it seems it can be even only winner in the very long term. Other ones are very risky, privacy ones can be threaten by governments.
Things to consider before investing good coin,
Market capitalization, it is the first thing every investors looks in a virtual currency. The Second, Maximum Supply, Certain cryptocurrencies from the very starting. cannot be mined but according to their market capitalization value. They might be holding top spots among all cryptocurrencies.