Actually, old Soviet shipbuilding placed quite an emphasis on crew comfort, or at least officer comfort. Soviet naval vessels were often full of luxury items such as pianos, fireplaces and comfortable leather furniture. On the other hand, they were designed for shorter mission lengths than their western "counterparts", mainly because the Soviet navy had very limited bluewater ambitions and concentrated on protecting its home waters; there was less overall need for accommodation space onboard for that reason.
An interesting question is whether the Romulans significantly modified the interiors of their battle cruisers after receiving them from the Klingons, one way or another (war loot, treaty transfers, industrial espionage). Klingons appear to be long-reaching adventurists, but Romulans could fit the picture of Soviet-style homebodies; quite possibly they would rework the ships to meet very different mission demands.
Also, much as happens in the real world when ships are transferred from a northern navy to a tropical one, there might be a pressing need to sacrifice otherwise vital systems for the installation of even more vital life support elements, comparable to air conditioning or heating ITRW. Klingons and Romulans probably loathe each other's accommodation standards for a good reason.
The final question is whether the ship design would allow for these as such logical or necessary modifications. Could corridors be widened at will? Easily, if the original walls are just simple partitions inside a load-bearing hull...