One of the issues that has stuck me many times is ui component cloning. The current flex sdk provides functionality to clone an object but not a UIComponent. I know there is a way to do that using CreateComponentFromDescriptor but it does not server the entire purpose and is not straight forward.
I think the sdk should by default provide a Utility to create a replica of a existing component. I personally feel this should be the part of the sdk itself. -- Regards, Saurabh