Zen's low marketcap is an enormous strength, to my mind. Of course something valuable can get even more valuable. But from what I see in the crypto space the really exponential increases in short periods of time tend to happen less once market cap increases. Just on the speculative side, I like the look of Zen.

As for what Zen's position in the privacy coin space, at this point I see only one main competitor, and that is ZEC, which has a much higher market cap. There are other competitors but I see them as either too small/immature/not seriously developed or have governance and development based entirely on volunteerism. I cannot see a project really working purely on volunteerism - Bitcoin is a sort-of example of this, the insane delay in scaling because competing vested private interests stopped development, and of course now most development is done not by volunteers but by coders paid by whatever faction they give their fealty to (eg Bitcoin Core/Blockstream). I don't like that route. I much prefer a scheme where some of the mining reward funds development.

That's what Zen has.

As far as future potential, I personally believe getting Zen included in a multi-currency mobile wallet will be important to fund adoption.