I'm with quazi on this one
specially the polygons
also GM had textured polygons
gradient fills is another idea down the line
games that draw all sorts of interesting geometric shapes that are player controlled in some interesting way
not just random shapes, but objects like characters that deform according to physics (soft bodies)
you could make scenes that don't lose detail regardless of how much you zoom
smooth animations with any amount of frames but no extra ram usage
basically anything you could do with a vector graphics program
granted, yes, those types of things would take some major math
but I agree with quazi that without some extra features canvas's feature set seems pretty sparse
even for simpler applications. not that I'm complaining, construct freakin rocks, but I noticed the same thing
I was trying to make a vector graphics engine with gm, but the math to convert an arbitrary arrangement of points into a triangle list totally slowed down the interpreter after about 20 points.
and once I added bezier curves (even rough ones), it was clear it wasn't going to happen. construct is much faster, I'd love to have another crack at something like that
filled polygons + layers + opacity + pixel shaders = heaven