Roberto started to analyze the document - "Ok, the sector 2 has already enough stuff around.". Looking to the sector 3, "maybe here, an attack might disable easily the accessing points to reach the docks. I'd start checking if we can give more strenght to this section. If this sector is well connected under sector 2 and 1, it will give to the structure more integrity.
Then, if there are enough materials, I'd connect the whole sector 1 to the 2 covering all the edges. First with basic reinforcements, then, another floor could take position above it, like the sector 3 currently does with the below. "