Secret Defense Formation Bonus
I was thinking if Supercell could develop a secret defense formation bonus, like if buildings were placed in some kind of formation, like 4 wizard towers placed up in a perfect square formation with Town Hall in the middle, the village gains defense bonus like Barrier where reduces damage from incoming attack, until one of the towers is destroyed. I think this will make the game much more interesting, where users needs to figure out the formation and possibly get an achievement too.