I believe that smart contract based altcoins are the future as businesses and companies become interested into them.
Therefore, the best altcoins that you could buy right now would be ethereum, ethereum classic, Neo, Lisk, cardano, expanse, eoS, and Qtum.
Yeah, Ethereum has platform for smart contract and lot of new coins are coming each day which are etherum based. Litecoin on the other hand is not too bad itself. Its is a very good project and they have just postponed the LitePay Project, which will in sometime restarted and will be a great success.