At the moment its better to keep ethereum than to keep altcoins because ethereum is a strong coin, its certain it will rise but we don't just know how soon. Altcoins on the other hand can give more profit if held but its risky at this time considering the market situation, altcoins are struggling in the market right now.
Ethereum is the best Altcoin and is currently experiencing a bad condition for too long the value is down, but many believe that he can rise again and grow better. Altcoin has risks and Ethereum also has risks, all of them have risks, it all depends on how we run and handle it. if it can still be profitable, it will be chosen.