On the one hand, the Vasudan civilisation had existed for 10 000 years, as Eishtmo said. On the other, we are told that they had to enter space a bit early due to the scarcity of resources on their planet. These two facts are made compatible by the third fact that the Vasudans seem much less divisive and warlike than Terrans: "The Vasudans are a civilization of philosophers, artists, and scholars... To the Terran outsider, Vasudan society appears convoluted and ritualistic. The Vasudans themselves may seem arrogant, treacherous, and superstitious. On the other hand, Vasudans tend to view Terrans as aggressive, paranoid, and stupid. " Warfare drives much of our techological innovation and consumes great amounts of resources, so presumably the less warlike Vasudans would not have developed the technology as quickly, nor have needed to. Of course, it must also be said that when the need arose (i.e. they entered into war with the Terrans, and then the Shivans) they developed their technology at an alarming rate!
As for the Ancients, who says their homeworld was within GTVA space? It may be that GTVA space was on the edges of thier empire, and they felt no especial need to colonise yet, so didn't bother exterminating and/or subjugating the Terrans and Vasudans. From the Ancient monologues in FS1, it sounds more like they engaged in subduing races who could offer them some threat (i.e. other spacefarers) than that they were concerned with subjugating aliens at the beginning of deveoping civilisation.