I am prefer to choose ETH for long term insvestment. ETH is one of the best choice after Bitcoin and so far its profitable investment for me. I have never invested in LTC and have never been interested in this coin.
If you have never really cared and invested in litecoin, you should start to care and be willing to invest in it now because if eth is just a potential coin and just behind bitcoin, litecoin will be spoken as a close brother of bitcoin, it has existed in parallel with Bitcoin in a very long time, the position of litecoin before the community is very solid. Especially in recent times, the development and recovery of litecoin has started again, investing in litecoin in the long term will have the opportunity to receive many benefits, eth seems to have a slow return, waiting to take longer than litecoin