The mazda's engine has direct
The mazda's engine has direct injection, while the honda's doesn't. That's a much more relevant omission than patting yourselves on the back about noting an almost insignificant tire diameter difference. It explains the better torque curve and driveability, as well as most of the MPG.
The HR-V's engine is extremely dated, has been used in the civic virtually unchanged for 2 model cycles, and ilets down the design. It is reliable enough, but is a poor match for this car, especially in the AWD version.
Anyone buying the HRV is going to be awfully disappointed when the turbo 1.5 from the new civic engines are put in the car much sooner than later.