I trade cryptocurrencies through my self-directed ira (see my post for more details). Basically, it is a very illiquid market, but with huge potential if you know enough about the new innovations in the different blockchains.

Here's what I look for to hold in my blockchain investment portfolio : independent implementations of blockchain, new consensus algorithms (proof of work, tangles, etc.), ring cryptography, and pay-for-use of a particular application (app-token).

Obviously, any number of these, the quality of the project and the devs and the community impact my investment decisions.

I can say that Steem has all but one of those criteria that I listed. If only ring cryptography were implemented ... sigh.