Moreover, it sacrifices another of the Star Destroyer's typical roles: planetary invasion or the ability to put boots on the ground. The ship lacks the fighter protection enjoyed by its close relatives, sacrificing it for armour and shileding that, we have established, are not sturdy defences in-universe.
I'm not even sure, from what we see, that the ship is capable of launching or receiving Lambda-class shuttles.
The vessel also lacks significant ventral hangar bays, and other sources have clarified that this is not made up for by the provision of replacement hangar bays dorsally or on either flank. The ship's reactor (which is what the bulb is) is more heavily protected in the ship's innards. It's reasonable to infer that this means that she is more heavily armoured. The ship lacks the aftward ventral bulb that distinguishes the Imperial and Imperial II classes. Into this milieu the Tector-class Star Destroyer is introduced.
