I see your points, very much so, but can one simply think of alternatives to "tweaking" the files? Take it as a challenge. Why not deny the enemy valuable planets, without them they can't even produce capital ships! Each faction has a way to gain them with ease, I dont see the issue. Im a huge, huge Empire fan but the point remains; Petro didn't make them the badboys they deserve to be, so lets work round it eh? Certain planets offer certain abilities, certain ships offer certain strengths, mix, match and total the competition.
If this still doesn't appeal to you then just modify the XML files or play a Mod. Though personally I much prefer the second option. Let the pro's handle the technicalities. . . .
Now, as for a personal point of view, I think Star Destroyers need to be tweaked. Maybe make them more direct? Add some firepower, give them some more HP and shield power, but reduce their speed. You gotta give them a flaw and with Star Destroyers; speed fits.
The Consortium however need no major changes. Weak armor and defenses, but huge and destructive firepower. Think of the Aggressor as a Broadside Cruiser, pumping out missiles. But instead of a spread effect its much more . . . direct. The Mon Calamari Cruisers are also a pain, their huge shield totals and abilities overly worked. But missiles penetrate shields, so simply put a Star Destroyer against it and sneak a few broadsides into bombardment position. Failing that, Tie Defenders work wonders against them, diverting fire and firing ion.
I think Star Destroyers should be aimed at Capital Ships, the top dog, but have a vulnerability to smaller vessels, say a fighter and bomber squadron?
These are but a few ideas and alternatives that I can contribute. Rather than rush to the XML or Modding section, try to adapt and change your plans.
Grand Admiral of the Imperial Remnant.
"This one is constantly thinking, analyzing, strategizing. He showed no fear, but was curious, studying me in turn."
"All thoughts are worth listening to, whether later judged to be of value or not."
"I have no qualms about accepting a useful idea merely because it wasn't my own."
"Butů it was so artistically done."
―Thrawn's last words