I imagine they were shaping gravity anyway they wanted to.

Judging by their ships, they have gravity generators which are small enough and have a small enough ratio of energy consumption to energy generation to be used in something like the Millenium Falcon.

Which would mean that from an Engineering point of view the option on the left would be perfectly feasible.

On the other hand it does make some sense to structure a combat vehicle as an onion with more mission critical sections inside were they are better protected and less important ones on the outside - you easilly have armour in between levels in that setup whilst in the setup on the left you would need to explicitly add rings of armor sectioning your corridors to achieve the same.

That said, in the Star Wars films we can see that the ship hangars with access to space have a "side" open to space and the "floor" side perpendicular to the radius line of the Death Star, which is consistent with the left side option and inconsistent with the right side one (where the opening to space would be on the top).

Probably left simply because The death star is big but I don't believe it's big enough to hide the curve