I think you should sell your LTC and wait for the altcoin price to go down a bit far. Then use the money you sell your LTC to invest in ethereum. Because ethereum is much more profitable than LTC.
LTC is also profitable actually, it's just a little slower than Ethereum, and what you are suggesting is a very good thing because Ethereum is still the king of Altcoin to date, so it is obviously a very good choice.