It's also got a different speed and weaponry, which means it was likely based on a different ship. An attempt was made a few years ago to adjust all stats to try to reflect canon properly, but balance issues were not worked out and the project was dropped.
Oh I understand balancing the game. Otherwise ISD's would have Hyper 6 or 7. But even at 300m its outclassed by ships its own size let alone 600m, only worth collecting. But I guess there are reasons, I would guess now becuase the larger size means it can cost more RM (and therefore double its valueless-ness)
Eh? The length of the ship is quite possibly the most useless stat a ship can have in SWC. It's more useful as a collector's item because of its comparatively low weaponry and speed (compared to more readily available ships of similar market value), not its length.
I think Icarus was referring to its lack of weapons/shielding etc compared to a ship half its size. However keep in mind the role of the Nebulan-B it was an escort vessel not a front line vessel. It was expected to protect convoys from pirates.
Due to the long tours of escort duty which is probably mostly boring the ships were probably provided with more spacious quarters and accommodations than is standard for a front line vessel in order to help promote good mental health among the crew.
To cut costs they probably provided it with fewer weapons than a ship of its size normally would carry. Sufficient to deal with any pirate but not necessarily sufficient to go toe to toe with line ships. In a military line it would more than likely be used as a starfighter screening vessel or light carrier if it had to be called to such duty.
Obviously the medical variant was specialized to be a hospital ship, something generally not kept on a main battle line but usually in a safe rear area to take care of wounded and dying soldiers. The spacious interior redesigned to accommodate medical bays, surgical bays etc. It might even go so far as to sacrifice hangar space etc.