The speed of light is pretty darn absolute. You can only go so fast until you are at that barrier and you either kick up to hyperspace and then you hit whatever boundaries that science has to offer. The hyperdrive as we know it is bazillions of years old according to the entry for the Duros, I doubt that tech is going to get any better. Blaster tech is probably topped out, the only thing that might happen is making the tech smaller so a more powerful blaster can be fit into a smaller package. Maybe a new weapons development could come along, most likely in the missile/torpedo department, but you can only get so much energy out of the Tibiana Gas. Laser tech might slightly improve in the same way, more power in a smaller package. But the photon density can only be pushed so far.
I'm not saying there isn't room for innovation but in game terms such innovations would be like the differences in firearms over the last 100 years on earth. The Colt Model 1911 is still in production and while there have been minor alterations in metals and manufacturing the design isn't much different today than it was when Browning designed the first one. In fact, many of those pistols are still in use. Modern firearms are made from more exotic materials making them lighter, perhaps more durable and a tad smoother to fire, but a lump of lead pushed by exploding gunpowder can only go so fast and transfer only so much energy. Be it a 9mm, 10 mm, or 11mm slug if you get hit by one in an important place it's unlikely you will be home for supper. If you really want to quantify those differences in game terms you'd be hard pressed to alter any of the numbers. You might make the newer ones more reliable in some way or the older ones less so. You might make newer ones more accurate but that's about all I could see doing.
The Galactic Republic was around for a long time and most of the pure science that drove innovation was done under it's more liberal attitudes. The Empire has clamped down and as such the kind of open communication that favors technological innovation is no more. Also the wealth of the Republic and Separatist worlds was pretty much sucked up by the war and 30 to 60 years isn't long enough to pay off those kind of debts. Such an economic environment isn't where pure research gets done. So the kind of innovation that would justify increasing a ships weapon damage by more than 1 point wouldn't be happening. Drastic changes to Hyperspace technology or even real space drive technology wouldn't get enough of a bump to justify changes to speed or hyperspace ratings.
Seems to me any new ships would be like our new cars. We see lots of special doo dads and gee haws and a slight improvements to MPG mostly by reducing the weight of the vehicle and precisely matching the engine size to the loaded weight. But can you say there really have been any drastic improvements in transportation?

