If you are suggesting that the pool operator hold the coins we mine and try to time the sells to maximize profit (ie if a coin goes down below it's usual value maybe hold it for a few days to see if it goes back up) I would be in favor of that. I'm definitely cool with more risk/more reward
imo it's not the job of a multipool to keep coins for a longer time than necessary in the hope the price might rise again. it's too risky.
If you want this, go with a multipool that allows you to withdraw the coins mined yourself, as opposed to auto-switching to BTC. There are several out there.