So I recently submitted a Vanilla theme called InterBlue (along with some other colors) to ThemeForest, and unfortunately they didn't accept it.
The reason they gave was that it didn't meet their quality standards and I should work on it more, and then resubmit it once I've made "significant" changes to it. I think a good place to start with that project is to redo the content area and the panel, not sure what to do there though. I think I'm also going to try and make it compatible with IE and fix some issues with Firefox and button padding, but I'm not sure how to do that yet. I think there's a way to use a specific stylesheet depending on the browser's useragent, but I'll have to do some research on that.
Another thing I have planned is to make it more customizable, without having to make the user use Photoshop. I was thinking in terms of making a transparent gradient image, using it as the header background, and then set a background color and use the opacity CSS property. Should be cool, and it will make some things easier for the end user.
I'm also probably going to look into use LESS CSS, which would open up further options for customizing the theme. For example, the background color I use in the header could be used for borders and some text, instead of making it all gray and stuff.
This week should be fun. In the end, if it's accepted, it will be so worth it, but if not, then I may have to look into other options for selling it or submit it for free to the Vanilla community, which will give me more backlinks, but I would rather be making money off of it.