1- Yes, it's possible, but i'm not sure about mobile device.
2- Using R0J0hound's canvas as third party plugin would cut the image in pieces.
3- Make interface to manipulate sprite, if you apply the effects like color, hue, brightness, etc. it can be done with WebGL. If you won't use WebGL, you might find Pode's plugins.
4- Yeah, basically using R0j0hound's canvas.
5- I'm not sure it would work, but webGL effects may apply with parameters interface in runtime.