Your comment makes no sense. An f1.4 lens is f1.4 regardless of crop factor, in terms of the brightness. It will have a depth of field like an f2.8 lens on full-frame.
Either way the same rule would apply to your 85mm f1.2. It'd be like a 170mm on micro 4/3, f1.2 brightness and depth of field like an f2.8
Olympus have announced a 75mm f1.8 for m43, coming later in the year. Will be much smaller than the Canon of course.