Thanks Roland, that makes sense. If I remember correctly Stage3D content is rendered behind the normal DisplayList. This does allow you to mix Stage3D content with standard components. I guess when taking this into account it seems like item renderers would not be the way to go.
What about narrowing down this use case and introducing a new component, maybe something based off of the DataGroup? This may be able to allow us to get something "out the door" even with issues related to z-sorting and accessibility. I know currently these components rely heavily on the DisplayList, but after looking at the Starling framework I really don't think there is anything in place that would prevent this from happening.
