This piece is hilarious and fun! It would really look great on someone's dashboard - or on the desk of a biology teacher or doctor. You could sell these easily, especially if you made multiple types!
One proposal: this might look a lot better if the exposed edge of the barbie-head (which clearly shows your cutting marks & looks just like unfinished plastic) were carefully covered with red paint - the shade of an anatomical model, for instance. It would get rid of that unsightly cut-plastic look and make the skull stand out even more!