Litecoin is still one of the best altcoins to make profit.
It's one of the good coins to invest for this year but for 2018 I'll say that stick back to bitcoin. @OP do you invested with bitcoin already? Before you ask for those altcoins that are good to consider for investing for this year, consider first to have bitcoin. No doubt that bitcoin is the best coin to invest but if you are not interested about it. Litecoin and ETH will be the best altcoins that you can invest and also add to that list Monero. These are my top priorities but it is followed by other altcoins.
Between bitcoin and Litecoin, I will definitely choose the latter. Because the price of Bitcoin is really too high, while the current Litecoin is currently only less than 350 dollars. But at the same time I also consider various ICOs and other altcoin.
ICOs today are just a bunch of collection agencies that wants to make money easily. But for this year there are some ICOs that catches my eye though most of them are really good only in the beginning when they are promoting their ICO and giving bonuses to their investors. I think ICOs for next year are going to be lesser since there are countries that are starting to become strict with their rules regarding crowd sale and this will make these altcoins that we mentioned giving a full blast.