reddit's UI in 2006 wasn't much better (interestingly enough, note the lack of a comments page). As responsive as mk and the gang are to the needs and growth of this website, I would be very surprised if the UI didn't get a major overhaul within the next couple of years, or at the very least a series of substantial changes that will redesign the website gradually over time.
Yes, I'm aware, and super important to note with your comment, Reddit's community in 2006 was also much different. It was very comparable to Hubski now. A site aggregator, that aggregated community and tech and philosophy. What happened? (rhetorical question)
Oh, believe me, I know. I still frequent Reddit just to remain a part of small true niche subreddits. You know, the ones where it isn't over 50% imgur links. Where discussion is still very real. Where the comments aren't reaction GIFs. I'm even a prominent figure in some, haha.
It's working well for Hubski, but I see how it makes sense for Reddit. Hubski has users share ideas and philosphies, and write poems and short stories. Reddit was also very intellectual (keyword: 'was') but it was centered originally more around technology and, and it's main purpose was aggregating. Of course, that has very little in itself to do with the decline. It simply enabled the decline. Hear me out here, as comments were added it opened the site up to a wider audience. And as it bloated, it became a dying star of huge numbers, and huge impurities. At this point, a majority of Reddit doesn't know** the history of Reddit, hell I bet they wouldn't react if I said "Alexis Ohanian" "Steve Huffman" or "Aaron Swartz". In fact, I don't need to bet. I know this. In my school, to most students, Reddit is "that site with the memes". It's no longer that site where people support each other to grow intellectually, and there's no longer a sense of community. It's too big for community, and there's a quote I read on Reddit a year or two ago: "The IQ of the group is the lowest IQ of a member of the group divided by the number of people in the group."** and Reddit is a prime example.
That only serves to illustrate one of the fundamental differences between reddit and hubski - hubski was created with an emphasis on users and comments, reddit was created with an emphasis on submissions and topics. I don't think success will be the same curse for hubski as it was for reddit.