Which altcoin are good for investment. First you need to know very well about the altcoin. You can also take help on some website. Such as coinmarketcap.com. I think ETH is very good coin. And you can go with ETH.
One can always go with Ethereum, but should never go with one single coin only Other altcoins worth buying now are NEO and Litecoin. Cardano is very promising, too.