I might be able to speak to this a little bit too, since we're using Stage3D and Starling extensively in
1849.
would you say in your experience that the Blitting seems to be the biggest bottle-neck?
On the PC, I've done games using standard display list (bitmap based and vector based), blitting, and stage3d. Blitting often beats old-school "display list full of bitmaps", but stage3d beats them both by *a lot*.
I haven't tried blitting on mobile, but I'd expect this to be even more pronounced, because stage3d doesn't tax the cpu nearly as much.
I have as yet got to get my head around starling as it appears that objects are added like old school movieclips and their X/Y's updated as opposed to Blitting that completely refreshes the screen each cycle with no physical objects. ... Although just typing all that I realise that all the games items have a UID so could in theory just update their Starling objects based on that ... (?)
Yeah, starling does have an API that's very similar to the old school display list. It's backed by raw quads (e.g. each Image instance is just two triangles with a texture), but it is nice that you can group things inside a container, and move or scale them together.
What I do sounds like what you describe: for each game object, I have a display object in starling, and my game code moves/scales/animates them, so that starling is only responsible for showing them on screen.
I also work with the Flash IDE (5.5) so the starling code demos blown my brain a bit
Wow! I'd strongly encourage checking out Flash Builder, or at least FlashDevelop! With Starling, you can't use vector art or timeline anyway, and those two are much more programming-friendly...