Great suggestion but you can also look for some good altcoins like ETH and XEM this two can also generate good profit for you in the long run, you just need to be more patient. A lot of negative news about cryptomarket right now but I think, 2018 will still be a great year for sure, lets enjoy buying more good coins.
Not only these three coins but currently we can find a lot of coins are available at reasonable prices. So What I suggest is instead of sticking to just these three go for few more to add to your portfolio to increase profit making chances. I don't want to suggest any particular coins because each person will have their own preference so you can just analyse some top most coins and also new good ICO's to invest.