Well, if you can't find a way to modify the durability of components, you could always try the "nosysdamage" FLAG. Any ship with it will not receive damage to any of its components. You would have to add that to every ship in the game, though.
The easiest way is to edit the race files, and give all the ships better shields. the shields have to be knocked out before any damage goes to the components / systems / weapons.
Alternately, edit the shield item files and make the existing shields all stronger.