Edit mode would be nice. It'd show handles around each object and hijack oncontextmenu to do something like Morphic. The handles would be a transformation widget (a better version of canvas.html#TransformWidgetProto.)

The primary use for it would be to do object layout (assuming that the graphics come from Inkscape / bitmap image editor), transformations and animations. Exposing the object's event listeners, frame listeners and keyframes for editing would be awesome.

Once that part is down, it could be extended for editing the graphics objects (and motion paths require a path editor anyhow.) That'd require "create object, add & delete & move control points", see canvas.html#EditableCurve and #CatmullRom for inspiration.

Also would need widgets for picking colors and building gradients. A custom gradient interpolator would be good (weighed color stops, then compile down to linear gradient stops.)

I can help you with it. It was already planned by me. :P

Hey, sure, please do.

I added you as a project member, it should give you the ability to commit to the SVN repo (I hope.)

If you have any questions, I'd be more than happy to answer :)