<canvas> has its own set of drawing functions (line, polygon, circle, fill etc.), would be a good idea to expose these to Construct 2.
I don't think SVG can be used with canvas, however, as those two are fundamentally different technologies. canvas is meant to be used as a drawing board to which you draw lines, circles and stuff with function calls. Perhaps a plugin which would read SVG file and draw everything, however that'd be terribly inefficient.
It is like disassembling a car and then re-assembling it on another spot.