In making decision over an altcoin, you should mostly rely on your experience on it for the best possible outcomes. If you have earned much profit already and the altcoin you are currently investing on right now, exchanging the most of it wouldn't hurt you that much. Just remember to leave some of it on hold so that if ever the value of that specific altcoin suddenly goes up, you wouldn't have much regrets. Since you've been on that altcoin for a while now, it wouldn't be ideal to compare with others that appears similar to it, you can just focus on it and keep updated on the market movement so that you may know if it's the best time to exchange or to buy.
but regret will be there when a long correction occurs. why not sell everything when the price is good instead of holding some to finally see only a long correction.
I honestly don't like it that way. indeed most people still use it in investing in altcoins.
when I sell at a price that I think is profitable then I no longer need to keep the asset. I will wait for it to correct again. meanwhile, I will transfer my money to another asset. trading trends will inevitably shift to other assets. like the current market momentum. we can see how each altcoin takes turns gaining its momentum.