Before there were TIE Fighters... image - Star Wars Rise of Hope mod for Star Wars: Empire at War: Forces of Corruption

There were V-Wings and ARC-170s.

"V-wings were some of the more recent spacecraft in the Republic Navy, and frequently filled the role as combat support ships. The small silhouette, high speed, and great agility of this fighter made it hard to target and a very effective ship despite its small size. They were later succeeded by the Imperial TIE Fighter and its variants, as well as the Rebel RZ-1 A-wing interceptor, all of which incorporated aspects of the V-wing into their designs."

"The ARC-170 was a departure from other starfighter designs of the Clone Wars era. Fighters such as the Alpha-3 Nimbus and the Eta-2 Actis were built to be small, fast, and maneuverable, at the cost of heavy weapons, shields, and hyperdrives. On the other hand, the ARC-170 was large, rugged, and capable of long independent operations."

As the title suggests, these fighters will be available before TIEs become the primary starfighter model of the Empire. The V-Wing will only be available from early tech Venator-Class Star Destroyers while the ARCs (for the Empire) will be buildable only at the first tech level. The Rebels can obtain them until they get the X-Wing. Since both starfighters are equipped with astromech droids, they will both have a passive in-flight repair. Compared to a TIE Fighter, the V-Wing will be faster and more durable but much less maneuverable. Compared to the X-Wing, the ARC-170 will be slower and less maneuverable, but more durable. While the ARC-170 can only be found in Imperial and Rebel Fleets, the V-Wing will appear much more frequently.

CREDITS:
Models and Textures: Lucasarts/Free Radical(Astromech on the ARC-170 is from YVAW's X-Wing which is from DICE's SWBF. Texture edits for the other starfighter variants were done my Nkorn)
Export: Jedi_Clone_X2
Rig and animations: Nkorn
Engine Particles: YVAW Team