Invest a little in both, LTC got some promising things in the roadmap, it’s hard as there’s so many coins out there, what I tend to do is what you should do with any portfolio and diversify
I don't agree with you that ltc got some promising things at the road map.
Litecoin acts like a living testnet for bitcoin, As they are using almost the same code( as I said, same code with small parameter changes, such as block reward and block intervals changes), which makes it a very comfort enivroment to try bitcoin features before they go live on the main net.
Lighining network, which is designed to be running at the main net bitcoin netowork to solve the scalability problem, is soon going to be live at the Litecoin network before it goes live at the bitcoin network, so people can test that it works, the damage that it can be done if it has any troubles to the litecoin network is much less then it can do for the main bitcoin network, the devs know it and that's how they use the litecoin network.
