So many coins to choose from!! I'll give 3, one for high, mid, and low cap to stir things up a bit! 

High cap - EOS, while there are issues with centralization, it's clear from the trading volume and the support it gets from overseas that this coin is going nowhere, a safe and profitable long term play. 

Mid cap - KMD, they've been around for a year and a half with a focus on building their technology and not worrying so much about the marketing. They are a platform coin for Dapps, DICO's and countless other things, like even including atomic swamps and privacy features. On the topic of privacy features, my low cap pick...

Low cap - XSPEC, if you haven't researched this coin yet I highly recommend you do, or if you only know about it from the FUD earlier in the year, that dev is gone with many new devs having taken over and bringing amazing privacy tech forward. Stealth addresses, ring signatures, natively built on the TOR network (unlike the other coins that pretend they are yet have exit nodes) with upcoming RingCT/stealth staking! Couple all that with PosV3 tech which means insanely fast/cheap transactions, XSPEC will essentially be a proof of stake version of Monero, much better for small remittances. This is a long term play for me, not a trade so the current low volume is a non-issue while the tech continues to be completed. Marketing can wait until the full product is built even though it's already a functional privacy coin, unlike most others.