I am experimenting with a masonry layout web site bringing niche news and cultural information on East Asia to a Western audience. I have chosen a masonry layout for the homepage because the site will be functioning as a microblogging platform pushing out several small updates daily (images, videos, tweets, texts, listicles, quotes). The masonry layout works fine, the only problem I have is that I am unable to come up with a non-obtrusive, minimalist design that doesn't look dull and boring at the same time. Currently, I think it pretty much does. Here is an item (representing a post or article) from the layout.
The sans-serif font is Ubuntu and the serif is Droid Serif. The colors are black #333, gray #999 and the accent color is purple #939. Notice that the items do not have separate graphic planes or borders, i.e. they are laid out directly on the background of the page (solid white #fcfcfc). The only visual separator between the items is a 1px dotted #999 border-bottom and a few ems of white space. (see screenshot link below)
If you take a look at the whole page (no header or footer, only the main content area) you will see that it is not very spectacular.
I have checked a lot of masonry layouts but I find none that doesn't separate the posts from the background by different colors or borders (like Pinterest) and still looks amazing.
How could I tweak the typography, contrast or visual seperation of the items to make things slightly more impressing without adding too much clutter?