Well it looks like Ethereum has already making significant gains already and the next price to test is $500. But I have not doubt that is even surpassed it this year, its only less than $30 dollar before achieving $500 although it looks like some resistance, but I have no doubts that around December it will be broken.
As far as for longer term hold, only bitcoin and ethereum is the best choice. Other coins are just for dumping like what happened to bitcoin cash. If you can still buy before it reaches $500 then it would be nice. But if you just prefer it to hold then is OK as well.