I just discovered your plugin and it looks really great. One thing that could make it even more better, in my opinion, is by adding an option to display a slider of the uploaded images.
Before, I used this plugin: http://wordpress.org/extend/plugins/header-image-slider/, but that seemed to stop working since 3.5 and hasn't been updated a for a while now.
I will try to see if I can somehow merge the functionality of that plugin with yours and see how it works. If it works, I will post it here, sou you can include it in a future version if you want. If I can't get it working, maybe you are interested to look at it yourself.