So if I got this right, the GTA will have the Orion from the very start? And the fisheads will make 3 destroyer in an attempt to rival the Orion??
Isn't that a bit too much? IMHO, I would assume the Zods first try to rival the Reliant or hte Orion is an attmpt to overshadow the Thanathos or Savior.. What ARE the GTA R&D and Design department doing? Sleeping?
Actually, the idea is that the Orion is a wonderful hull design. The various components are very modular, allowing systems to be removed and replaced with more advanced systems. This follows from FS2, where beam cannons were easily attached to the Orions, so easily that most were still in operation, while the Typhon couldn't be modified as easily.
Couple this with the fact that fighters have removable primaries and shielding systems were easily attached to all GTA fighters, and we can make a leap and say that GTA R&D was focused on creating a modules that could easily be attached to older hulls, the Orion in particular, and thus keep up with whatever new designs the Vasudans came up with.
The Vasudans didn't quite get the point. The Thantos was mearly a mini-Orion (AKA, a Reliant basically) that, of course, wasn't a match for the Orion. The Savior was designed to be a match, but they didn't understand the idea of modularzation of major components and so eventually the Orion was simply refitted and overpowered the Savior, so the Vasudans decided to go back to the drawing board and cranked out the Typhon, which was more than a match for the modern Orion (as evidenced by the Vega Engagement).
If the Shivans hadn't shown up, I feel confident that a refitted Orion would have forced the Vasudans to redesign, again.