I've been mucking about with Master of Orion II again in my spare time (v1.31 patch) and came across the COrion2 save file editor. It lets me change anything about current players, ships, systems, leaders by editing the save game files.

COrion2.zip (May 1997)
README.NOW - this is the readme file
TIPS.TXT - some tips the author wrote

Unfortunately I haven't found a way to do what I really wanted to do... edit the space / cost starting values for various technology items. You see, I'd like to make it so that phasors, black hole generators, and stellar converters are a good bit larger then they are now - as those (3) items are pretty much super-weapons in the late game. A ship with banks of Auto-Fire Shield-Piercing Phasors, Structural Analyzer, and High-Energy Focus can easily decimate multiple opponents of the same ship class (especially if combined with the Achilles Targeting Unit). One of my late-game doom-stars has 180 Shield-Piercing, Auto-Fire Phasors which is 180 [quantity] x 20 [damage] x 3 [auto-fire] x 1.5 [h.e. focus] x 2.0 [structural analyzer] = 32,400 points of potential damage output. Even late-game doom stars don't stand up to that kind of abuse, even with Xentronium Armor (1500 base points on a doom-star), Reinforced Hull (triples structure points), Heavy Armor (triples armor points) a doom-star only has around 10,500 points. Using a Damper Field reduces the damage taken by 75 percent, which would possibly allow you to survive a mauling by that ship design.

Shield-Piercing Auto-Fire Phasors are a seriously powerful weapon...