I heard that Blizzard would increase the range up to 8 yards but at this moment the tooltip still says it has 5 yards range. It's very annoying when I use Kill Command to a moving target, 90% of the time it says "Out of range" and I have to spam the button until it's done.

My suggestiong: Kill Command gives your pet a buff that increase its basic attack damage X amount for a few seconds (6 would be nice because it's match with Kill Command cooldown).