You could achieve that with a child theme, so your tweaks won’t be overwritten when updating the theme. Here are some guides in case you haven’t made one before:
http://codex.wordpress.org/Child_Themes
http://op111.net/53/
http://vimeo.com/39023468
In your child theme you would add a thumbnail function in content-single.php to output the featured image, and style it as needed with CSS.
More about the function: https://codex.wordpress.org/Function_Reference/the_post_thumbnail
It would be great if a featured image at the top of the post was built in, like most themes. So that people don’t have to be a programmer to get it to work.
Otherwise, I love the theme!
Any chance that will get updated?
jimpicariello – nope, not in this theme. Sorry!