your portfolio must be diversified as how you see the market . however you should have minimum risk of your money. high volatile coins and tokens must be placed with minimum % of allocation of your portfolio. it is better to keep 50% of your portfolio as bitcoin. 30% as ethereum and rest of 20% should be altcoins .
Splitting all the coins you have makes a good decision at this point, many things might surprise you if you have only one coin. all the declines you can't stand it will continue to happen if Bitcoin continues to fall. I have coins held up until now with a pretty good amount. this is all a long thought until now.