Sensor wise, about any Canon camera is great for macros. It comes down to the lens you want to use (focal length dictates working distance assuming a 1:1 macro lens), IS or not, lighting, and the features of the body you use. An articulating screen and live view are very, very nice tools for macros, as is pretty decent higher ISO values in case you cannot get auxiliary lighting on the subject material. The rest of the equation will really be the lighting and lens.
I wish the 7D2 had a tilting screen, these would be easier to get, even when I use live view.