Imbalance 2 displays the beginning of each post on the main page. As in all themes that display post beginnings, all HTML tags are stripped out; so no links, no formatted text, and no regularly inserted images. To display images on the front page, you need to set a featured image to each post, or copypaste content (including image code) from the HTML editor to the Excerpt module.
As for the header image, when you change theme the image you had uploaded for the previous theme won't work. You have to upload a new one from your computer (in Appearance > Header).
Yes, it's somewhat like Inuit Types. The main page displays excerpts of your latest posts (as well as stickies, if you've got any), with optional images as explained above. The difference is that in Inuit Types you select one or two columns while in Imbalance 2 you select fixed layout (four columns) or fluid layout (as many columns as will fit in your screen). Other differences: a) no sidebar - header and footer widget areas instead; b) narrow header image, top nav menu next to it, in one or two columns instead of a row.