The practice of downsizing older ship designs was a familiar practice to the Galactic Republic, and in particular, Rendili Star Drives. The separatist Providence-class cruisers, in which Rendili had a significant hand, was designed and offered in two drastically-different sizes. Earlier than this, the dreadnought-class heavy cruiser of Katana-Fleet fame could trace its design lineage back to a scaled-down Mandalorian Kandosii warship. However, this practice was not exclusive to Rendili, nor were they the first to do it.
Vaufthau Shipyards had collaborated with Rendili to produce the two-kilometer long Invincible-Class over three millenia before the Battle of Yavin. While imposing and effective on their debut, they were underpowered, overcrewed and soon proved ineffective against smaller vessels and starfighters. A few centuries later, Vaufthau would try again with a clean sheet, bringing in Corellian engineers to design a smaller successor to the Invincible.
Clocking in at just over nine hundred metres, the Invulnerable-class heavy cruiser was built around a heavily reinforced and nigh-indestructible central spine, giving the vessel impressive durability in theory. However, many of the components were substandard: half the drives were auxiliaries bolted on when the main system was revealed to be underpowered, and the innovative double-reactor proved temperamental and inefficient. While the ship's core elements were robust, the complexity of individual subsystems meant damaged sections often had to be stripped back to the spine and rebuilt from scratch. Once Rendili's much more robust Dreadnought was released onto the market, there were no two identical ships of the Invulnerable class in the Republic Navy. Come the Clone Wars, some of these ships would see action but most would just be retired, sold off or even just discarded into boneyards, where pragmatic rebel agents would eventually tag them as semi-usable vessels in later years.
The two Invulnerable-Class heavy cruisers demonstrate the diversity in loadout and designs these ships have accreted over their long service lives. 'Beast of Bracca' on the left sports a purely offensive bearing, retaining its forward missile launchers and tenuously supporting a total of eight heavy turbolasers. 'Katana 2-2' is a carrier: more recent refits make the ship a little more capable, with overhauled drives, a new reactor, lighter and more reliable armaments and a formidable hangar bay.
(This was another lockdown build cobbled together from Saturn 5 Lunar Lander parts and other pieces, with the original build on the far left. Renders available at
https://imgur.com/a/qgC3IkG )