If we look at those two altcoin, I prefer investing in Litecoin because for me it has a higher success than Bitcoin Cash. Here's why I don't think Bitcoin Cash have a higher success, BCH don't have segwit, and it is a hard fork coin and huge of its supply is pre mined that is cheating while Litecoin started from scratch and still faster to transact compared to Bitcoin Cash. But overall I would still choose to invest in Bitcoin, yes core developers are trying to solve scalability issues, they implemented segwit to reduce the transaction fee and to make it faster to transfer but still not enough, now they are working with lightning network and hopefully it solves the problem that we are all waiting for.