In my own opinion about this question, I think it is wise to hold altcoins despite the fact that altcoins rely mainly on Bitcoin, It should be held as well besides altcoins can add a huge value to your income and increase your profit whenever there is an increase or change in the price raise. In as much as the cryptocurrency is involved, one will always need to have altcoins to make the system keep running while there is a standstill or deep in Bitcoin.