In my vision of miniaturization technology, it applies to all components. I might create a new Version of each component that requires 90% the space but costs twice as much to research. The next Version would cost twice as much as the previous component but require 80% of the space. And so on... That is one way of doing it.
In order to implement this, you might start by adding additional levels to ALL technology tracks that lead to components. Then, create higher Versions of each component that require less space.
This is not really a complete solution, though, because the tech costs might not increase fast enough to insure game balance. Instead, you would probably have to create additional technologies for *every* component so that you get a steep enough slope in the cost vs. size curve.
Play balance is going to be a big factor. Before a project as big as this was attempted, it might be helpful to determine an equation that could be used to determine firepower vs. weapon abilities (shield piercing, armor piercing, etc) vs. resource cost vs. size. Then, balance the entire original tech tree. After that.... Well, that's a lifetime of work already. But after you did that, it would be trivial to write a computer program to generate additional technologies and components so that you could add, for example, ten levels of miniaturization to all components in the game so that after investing a HUGE amount of tech research, you could have components that are at least 10x smaller.
Hmm... now that I've written all this, it seems rather foolish to create additional component-specific technologies that only yield a smaller Version of a single components. Instead, you would research a technology and gain a reduced Version of several components. Still though, game balance is the hard part. Although, it is readily granted that the weapons aren't terribly balanced now anyways.
