some coins I really like which have not shown their full potential yet are:

1)TenX: it's one of the few projects that has an actual product which people are already using and it's the leader in that sector (debit payments directly through crypto's). There are other competitors out there as well, like TokenCard and Monaco, but non of them is as advanced and forward looking as TenX, in my opinion

2)XRP: XRP is an obvious player because they already have a huge network where the coins are already integrated. They are basically facilitating interbank transactions (which means that most of their clients are Banks) and that helps these banks reduce costs that are usually due to moving money even though they don't really have to

3)ETH: which is kinda obvious, but it's the most adopted smart contract network out there, which offers a great infrastructure to build any sort of decentralized apps. There are as well many updates coming that will make the network even more strong and that will ultimately drive up the price