At my default browser size I can see 8 items on Monocle at a glance and 21 on Hacker News. I'd suggest, at least, reducing the size of the information about the submitter, number of points, etc. When scanning HN I very rarely look at those.

I don't find avatars add to the conversation mostly because I don't first look to see who said something. If I read something interesting I might look to see who wrote it.

I'm not sure what the thumbnail graphics from the article are adding.

One thing I like about HN is the choice I make between reading the comments and reading the article with no framing.