That's actually an interesting idea. It's simple, and yet there don't seem to be any immediately apparent problems, outside of coming up with a logical explanation that justifies the game mechanics in believable enough quasi-real-world terms. At the very least, it's an idea that sounds decent enough on paper--which is generally the best-case scenario when you're dealing with fans sharing ideas in an Internet forum.
The idea also got me thinking, and I went ahead and typed it in as the following wall of psychobabble. I seriously doubt that it will ever get anywhere, given the sheer scale and complexity of it (it
is a wall of psychobabble, after all), but maybe it'll inspire someone else. Or something. Maybe.
Oh heck, all I know is that I gotta do something about my perfectionism when it comes to these sorts of things.
Personally, I think it'd be neat to have an evasion system in place. Basically, each ship would have a maneuverability rating that factors in to whether an attack fired upon it actually connects. Naturally, smaller hulls would have higher inherent maneuverabilities, while getting a large hull to dodge something would be rare, and huge hulls would be all but impossible.
There would also be components that improve maneuverability, in the form of side thrusters, automatic evasion systems, teleporters, etc. These components would require less space than the typical defenses (I'll admit I'm not sure about cost and research), but only for tiny and small hulls; the required space and cost would increase dramatically with larger hulls sizes, as a measure to keep players from just cramming tons of components on them. This would result in the tiny and small fighters relying more on evading fired shots entirely (but being pretty much screwed when they are hit), the large and huge battleships relying on the typical defenses to neutralize attacks, and the medium-sized frigates being able to mix and match.
Of course, if you're going to have increasing degrees of maneuverability, you'll need increasing degrees of precision. While research, size, and/or cost of weapon components would likely need some tweaking as a result, a general rule of thumb would be that mass drivers would be the easiest to evade, with lasers being more difficult to avoid (due to the sheer speed of their delivery), and missiles being the most most accurate weapons (thanks to their guidance systems). In addition to that, each iteration in a generation of weapons would more precise as any earlier iterations in the same generation. For example, Laser V would be more precise than Laser II; and while Plasma I would be less precise than Laser V (due to being the unrefined initial installment of a new generation), Plasma III would be equally, if not more, precise than Laser V.
There'd also be ship components that increase precision "across the board," in the form of targeting systems, tractor beams, temporal distorters, etc. How effective these components would be, in relation to the maneuverability components, is not something that can be currently answered, though; it largely depends on how things work out with version 1.2. Additionally, the cost, size, and research for these components are probably the murkiest game-balancing issues in the entirety of the evasion system, and would most likely be figured out only through play-testing.
Now that I look back on all of that, it's likely that if such a thing is ever to happen, it would have to be through either an expansion pack (and as one of the main features, I imagine), or as part of the combat engine in GalCiv III (which is not anytime soon).
I think it'd be worth it, though: part of the appeal of GalCiv II's whole ship customization thing is not unlike that of managing each of your batallion's units (fleets) and characters (ships) in the Ogre Battle series of games. Considering GalCiv II already has your basic hitpoints, attack, and defense stats, which are common to literally every console RPG ever made, implementing a sort of "dexterity" stat would serve to augment this resemblance, and capitalize on it's appeal.
That, and we're gonna have to come up with
something in the event that 1.2 doesn't solve the attack versus defense issue, or introduces any unforeseen problems itself.
And yes, I'm finally done! Thanks for having taken the time to read all that; and if you feel you just wasted your time doing so, then you can at least take satisfaction in knowing that I wasted so much time typing this thing that it's downright shameful.