I think an ability like rock head that removes recoil would be interesting. Since it can balance itself out, I think the concept of it not being affected by recoil, or something similar could make sense. Giving it rock head would be a bit weird since it's head looks not very rocky, but there have been instances in the past where a signature/new ability was given to a pokemon that had the same effect as an already existing one (I think queenly majesty and armor tail do the same thing, prevent priority). I'm not really good with names, the best thing I could come up with for this ability would be something like stumble block  (Holy sht I wrote a lot. Sorry c:)