For me, ETH is a more reliable investment coin than LTC, but perhaps it is worth sharing the investment between these coins.
I would also prefer ethereum, but crypto currency is a very unpredictable thing. We have seen a lot of examples of how a very good project is losing value, and a useless project is growing very fast, so you can expect anything.
I completely agree with your words about the unpredictability of crypto currency. But the fact is that among all coins, the etherium has a greater potential than anything else. And first of all, thanks to the erc20 protocol.