For me it's ethereum. 2nd on market cap and big gains.
I will too go with ETH as one of the safest and best bets for this year like last year . Also along with it there are couple of more good coins as suggested by my friends were Ripple, ZCASH, Monerao and Dimcoin . Also considering that people have now largely started investing in altcoins due to its current cheap price with good future prospects can yield some real good profits in coming time.