I think now better to holding altcoins. Market doesnt be falling always, so soon situation in the world of cryptocurrency will change. I hope 2019 will bring us good news. Anyway at the moment price of altcoins so cheep so need wait.
Holding is better. The market small falls happen, but I do not think that they will last for long. The period, when the cryptocurrencies will grow fast again, is coming soon. Therefore, do not sell the crypto.