Interestingly enough, I think BTC has a lot of room to grow this year. With creative complementary technology, like the lightning network, there is no reason why the price of BTC won't continue to rise in 2018, especially with all of the attention it's getting, even in "mainstream" news.
Ethereum has become the basis for so many projects that while it's been unstable in the past, has now become a staple in the cryptocurrency community, while maintaining a price that on average keeps up with the growth of bitcoin.
Raiden network has a lot potential to being essential in future blockchain projects and will likely become very popular when their beta testing has completed and the final product is released.
Dragonchain looks very promising. Also, it's one of the few ICO's located in the U.S., and within the highly-regulated state of Washington, adding a certain level of trust to the project.
Litecoin has been slowly but surely gaining momentum in price over the past six months. I think as we see more companies partner with Litecoin in 2018, the value of LTC will continue to increase exponentially.