I would surely go for Ethereum over Litecoin for the reason that it is more popular in this industry. The reason might be shallow but if you are not new in this market, you would understand my point at the first glance. Popularity makes a crypto strong since its market value is dependent with the demand and supply. If a coin is popular, demand would be high as well as the market volume which makes it a better investment at this aspect over LTC. But still, LTC is a good coin. It is just that I believe that ETH is a better investment.