Hmm. Thanks for writing. Made me consider possibly switching/exchanging few coins in a portfolio.
Regarding Bitcoin itself - for now, it's probably to coin to hold money in. Yeah, it is volatile, but look at its history. Drop that is happening now is nothing surprising. But because Bitcoin is top-one & most of other coins follow it.
Thus no matter how big % of all your coins are in Bitcoin, it's definitely not more risky than rest of coins. .png)