I'm curious. What kind of middle values between (accidental, intentional) would we be talking about here?
It could be argued that God was smart enough to author the Law of Gravity, which saves Him from the chore of pushing every leaf to the ground.
The same could be said for Evolution: God set the rules then set them into motion.
Perhaps God no more needs to tinker with genes than He needs to use his supernatural powers to bind nuclear forces together.