To create your own desktop interface would require advanced programming knowledge and understanding of the X11 display server. However, I recommend you take a look at using LXDE or XFCE as both can be customised to create a relatively unique looking system.
Hello there tleicman. This is question of yours is a very good one. It is actually a fairly popular idea to create your own desktop environment. I did research on it for the version of my system that will be coming out soon. Although to code from scratch is very difficult requiring specialized knowledge, you can build a simple lightweight de by following any of many online tutorials. Personally I prefer this one:Link
You can see how clean such a desktop is by scrolling to the bottom of that article.