Adding Instances would be a god send
 

Having instance functionality would be hugely beneficial. I create many canvases when wireframing sites and after a while it becomes intolerably slow in opening, closing and navigating. Most of my elements are simply copies--being able to only store these once would dramatically increase the speed at which the program handles a document.

PLEASE ADD INSTANCE FUNCTIONALITY AS SOON AS POSSIBLE.

Thank you ,
-Davis