I can think of a couple of altcoins. Some of them which I am holding are Coss, civic, powerledger, storj, whitecoin,
LBRY credits and elastic.
These are all good altcoin. Currently I recommend you pay attention to the ADA, PRL which is the atlcoin technology with good community.
PRL plans to launch mainnet in late May.
ADA will launch its token in Q4 2018.