U.E. Osprey was the true successor of USF Courage.
The desire to replace aging USF Courage had been there for thousands of years. However, with fractured United Sol, the steps could never be made due to lack of R&D fund.

After formation of United Earth, the first step they took was developing a new cruiser to replace USF Courage.

On year 10248, Venus R&D division unrevealed U.E. Osprey. It was a ship that was meant to replace USF Courage from the beginning. Osprey inherited most of advantages of USF Courage while improving its shortcomings. The most major positive aspect of this cruiser was that it cost only half of cost compared to USF Courage.

U.E. Osprey was welcomed and was embraced warmly almost instantly as soon as its blueprint was released.

Major differences between UE Osprey and USF Courage are as below.

The first was lack of armor plating which was what made USF Courage cost so much. However, US Osprey still boosted good armor by utilizing new alloys.
The second was lack of windowed quarters on UE Osprey on surface. All windowed quarters were located on front behind adjustable doors. Windows had always proved to be a structural weakness yet desired in peaceful times. This was a compromised move.

UE Osprey was also the first space vessel to implement a modular ion engine. The engine featured 96 smaller, isolated, ion engines. What this ultimately meant that the ship’s engine could not entirely be disabled by a lucky shot from the rear when shields were down.

The ship’s firepower was also increased due to increased number of turrets. The turret itself was an improved model to improve tracking as well.

The only aspect USF Courage was objectively superior was its armor. However, UE Osprey matched USF Courage armor in its efficiency while having far less thickness. Additionally, optimized shield arrays on UE Osprey meant that the ship was superior in all aspects compared to USF Courage.

Development

It was believed that many of the ship’s features were inherited from VN Cecilia. While VN Cecilia was a clearly superior ship to USF Courage, its construction cost was far more with far too many non-standard parts required. UE Osprey solved all of its manufacturing issues.
Coincidentally, the lead designer of UE Osprey was Kisia’s daughter, Ciska Vlues and the lead designer of VN Cecilia was Kisia herself.