Bitcoin, Ripple, Ethereum, Waves, Monero, Litecoin are the best coins to hold for a long term as it has a great development team who are busy in making their coins better and better so it would be an right choice to hold all this coins.
Yes all these coins are profitable in the long term. Especially I will prefer Waves, Ethereum and Litecoin all these 3 coins will give an unexpected profit in future. Ripple and Monero not sure but Ripple is a good coin for trading. Bitcoin is evergreen coin if you do not hold any bitcoins then it is a big loss for you. I am holding all these coins and including NEM.