Fortresses generate with Battlements

Basically, along the supports on the long bridges which generate over lava, there would be a 25% chance of a battlement to generate on top of the bridge. 

These basically are towers which break up the sameness of the fortress and allows for quick shelter form incoming projectiles. - They are no safe haven though, since at the top there is a Blaze spawner which will spawn blazes to attack you. There is also a loot chest on top to encourage players to battle the Blazes to get the loot.