So, I've been using Imzy for a few days now. Here's my front page, for visual reference. Here's what I can tell:

Posts (both outside and inside) are clunky, taking up a lot of unnecessary space to describe the same amount of data, comparing to Reddit and Hubski. This holds up for both the feed and when visiting a community (the local analogue to a subreddit). It's fixable and won't take much, but it's never going to be as neat as the two aformentioned forums, given Imzy's current design paradigm (900px-ish, with almost have of it off-post taken to display links to communities one's "participating" in). The fact that the post list is often interrupted by "WE RECOMMEND THIS COMMUNITY FOR YOU" is not helping the feed.

The button to tip the poster takes more priority in the design than "report" (which is hidden behind a click-openable menu). I can't point out why, but it doesn't sit well with me. On the other hand, Imzy does well to remove the downvote button: if they want to facilitate a friendlier environment - their stated goal - then that's the way to go.

The whole of Imzy's communities, even ones that would usually generate some interest - like Technology - is quite inactive, both in terms of comments and whatever the local likes/upvotes are called. Release of a new Android app update, for example, only has 19 "hearts" - and that's a community you're subscribed to by default (you pick additional to start with right after signing up). It is, perhaps, a matter of time, but for an advertised "anti-Reddit", it's not a promising start.

Communities themselves are rather clunky. All the important details - rules, description, links and mod ("leader") list - are hidden behind separate tabs, each - their own webpage. Given the design paradigm, they would have to hide it in a drawer, but seeing how slowly the tabs load (there's nothing to accelerate that, despite there existing libraries for that), one loses interest well before getting to the very end. It's odd to see things this important hidden away behind anything other than a hover-openable panel.

One of the advertised features suggests that, given the tip mechanic (which is attached to your credit card), artists can communicate with their fans and, at the same time, thrive off their financial support. I had no chance to test that, but there are some artist-based communities that are in the top 25, activity-wise.

People there seem to be aiming for constructive and positive exchange, judging by the comments and the replies that I've got.

That's all I can say. I'm going to check in every once in a while to see if there are any major updates, but I'm not going to take part in it at the moment.