A real mouse would be cute but I wonder if nowadays a computer mouse is a mouse in its own right and people may not link a furry mouse with a computer mouse. I think it looks fine with the mouse you've drawn - just make it symmetrical and maybe add a short squiggly wire coming out of it. I think its as good as any professional image.:icon_thumbup:
If I was told to come up with an image for mousemat printing I would have come up with the same concept!