Altcoins are no longer so dependent on Bitcoin as it was last year. I think it's entirely possible for a coin to develop even if BTC is on a dump.
Yes, altcoins are not depending on Bitcoin. But the investors are. The investors are following Bitcoins movement and from there comes the whole transition to alts.
I don't think we will see any altcoin mowing separately this or next year.
Check out WAU Coin, its an appreciating monetary unit that has outperformed almost everything in 2018. The devs of WAU Coin are releasing NUMA soon that will be totally untied from bitcoin and will rise in pairing from usd. Very exciting stuff is happening in cryptocurrency despite the darkness from the crashing in major coins and media