I sugguest you to buy EOS as it is based on proof-of-stake and is also one such alt-coin for a good long term investment. If proof of stake isn't much of concern then ARDR is what you should be HODLing as the team behind the coin the NXT coin team (JELURIDA) is pretty good and the project itself holds much future business based use-case.

We got an airdrop coming up guys... IGNIS coin to be released on 1st of Jan, can be received as airdrop if you hold NXT tokens on 28th Dec 2017 as a 0.5:1 ratio.

Buy in some NXT to receive your IGNIS, note that this new coin will be listed on Bittrex too.