[PvK]

The suggestion has merits and could make an interestng mod.

However, if the weapons shrunk by a meaningful amount, isn't the situation still about the same? A higher tech ship will have more of the same weapon, doing more damage, instead of the same number of weapons doing more damage. Refits to new technology would still be desirable, but would be more complicated, since the changing component sizes would make more room on the design.

Seems to me the larger problem is that the research costs are pretty small and jumps in component abilities are pretty large. In the standard data set, without High research costs, it's just too quick to develop high levels in most techs, and to get to "the end" of them. In my Proportions mod, the lower levels are used quite a bit, simply because "waiting to get the highest level" means years and years of dedicated (and often inefficient, compared to lower levels of other techs) research.

PvK