MarelliIt is, but quite a minor one. I dont think it would really turn outcome in the favor of defenders. And forcing players to maneuver instead of blindly rushing ahead in stright line is definitely good in my opinion. Of course, there would be some tough nuts to crack, i mean OP's located in landscapes making them harder to break in, like Ginti or Demon's Crossroads. But again, towers would have area of effect, which makes their impact limited.
and forcing the attackers to maneuver around them is not an extra benefit to the defenders? :p