1) They start with more Star Dreadnoughts. Especially the two at Coruscant. They are nearly impossible to kill, especially with power to shields. I remember one fight where I had a dozen plus Katana dreadnoughts pounding away at one with power to weapons on, and after about 10 min of continuous bombardment its shields had only dropped by about two thirds.
2) This is the most important one. The NR is much much much more mobile. With some quick conquests at Eriadu, Denon and Druckenwell with the Sluis Van fleet, the Hydian Way and Corellian Run suddenly provide the NR with a superhighway of major trade routes they can use to swiftly react to any attack. Coupled with the fact that most NR warships have Class 2.0 or better hyperdrives, the NR can strike quickly and reinforce quickly nearly anywhere in the Galaxy. On the other hand, the Katana fleet is completely made up of Class 4.0 hyperdrive ships, and the Empire's fast ships (Star Destroyers) are not numerous enough to strike at the NR without dreadnought support. Added to the fact that the Empire does not start within conquering distance of any trade routes besides the Branxant Run, the Imperial fleet cannot respond to NR attacks well and also is very slow to mobilize.
3) NR starts with both more income and proximity to even more income. Several powerful planets are very close to large NR fleets (Corellia, Corfai, Denon, Eriadu) while the only fast opportunities for Imperial expansion are Bandomeer and Muunilinst. NR's great economy plus the shipyards at Kuat, Coruscant and Sluis Van means the Imperial Fleet's superiority is usually short-lived.
While each of these advantages are relatively small, they all add up.
My suggestions for balance: Some more Star Destroyers for the Empire. Preferably Imp-II's, since they have the Class 1.0 hyperdrive. Just adding 1 or 2 of them at, say, Bilringbi would, I think, balance the campaign out nicely.
Edited by Stormhawk, 11 September 2010 - 01:30 PM.