My biggest frustration with Zero is the lack of focus on the little things: 1) the website still has a bunch of broken links or empty areas; 2) STILL no road map; 3) very little promotion from the dev team on social media; 4) minimal interaction with the community.
You can have the best crypto currency on the market, literally code written by a god, but it doesnt matter if you dont commit to dialing it in on the small things b/c it will go nowhere. There are countless examples of coins languishing for this reason.
There are many millions of dollars on the line, but too many dev teams dont understand these basic points or think they are above marketing, promotion and clear communication.