if you want to invest in altcoins, this is the right time for you, because all altcoins are very cheap, buy good altcoins like the one below:
1. ripple
2. cardano
3. Holo
4. nem
5. dogecoin
I don't think dogecoin is worth investing. In fact, the risk of dogecoin is very high. I don't even dare to buy it. I suspect it may die at any time.
I think the most potential and worth investing in the five altcoins recommended by OP is cardano.