PopupTarget, I tell you what, I'll go down the road and tell the guys that built Hubble they did it wrong. And Chandra. And Spitzer. For that matter, any and all space probes ever made. Heck, I'll phone up Russia and ESA to let them know they have had it wrong all this time as well. Glad you could clear that up for us. (big wink!) Sorry about that, couldn't resist.
We are talking *space*. Water naval ships generate *more noise* to interfere with their *sonor* due to the medium they are in. You know, water. When you are talking space craft, space craft noise/interference becomes a serious non-issue at any decent power range (to run your sensors). That's real life space science, as of 1980 technology.
The medium your sensor platform is in really changes what you have to overcome to get good data. For space craft, the medium they are in is a near vacuum, meaning they have a lot less problems then earth side. Of course, they have more hard radiation to worry about, but since you have to worry about that just to have your craft work in that medium in the first place, then its usually a "done/handled" issue. Either you want that kind of radiation (so you let it into your collector and just protect your 'tronics) or you aren't (and therefore shield the important bits as you would for any other component on the craft).
Now, there are certain things that you can be interested in, where you have to take into account the *instrument* housing. But adding another collector of that information improves your data, regardless of if you are just cramming it into a twin into the same protective tube (hull), or putting it on a follow pod. Indeed, it is common practice in remote sensing space craft to split your sensors across multiple craft (meaning you have *many* follow pods). This is not due to a bigger craft to hold them all causing any interference in their data collection, but rather, it is to keep the size of your needed platform down, making it cheap to launch and being able to keep the instruments and recorders powered (smaller individual sensor "packages" means they are easier to keep powered off of batteries when they are lights out --- Power generation is the true design limitation on real world space craft).
Additionally, adaptive techniques are well established for those times you are stuck with housing/mother craft interference.
Adding sensors always scales in space applications. Always. Whether its gravitc, EM, solar particles, whatever. The more sensors, the more info you yield. It's not literally scalar (ie, 20 sensors doesn't yield a x20 science data increase over 1 sensor), but we aren't trying to get down to that level for GC, are we?
Now, we can ignore that if you like, but by limiting any hull size modifiers for sensors to only minorly scale (to cover the extra infrastructure required for that hull size) would at least allow bigger ships to gather better local intel (more sensors means they will let the user see things further out from that one craft). This is only going to improve the *user's* gaming experience, isn't it? Bigger ships can see further because they can be crammed with more sensors. Finally, a real reason to build a big ship. AWACs.
re: Crew and life support
Life support was something I thought about. But, as we don't know about crew requirement's and at what point automation allows 1 person to do the work of 10, I thought it best to skip over, for game reasons. Power generation, by itself, can actually keep things under control. Then there's the whole different life form things (who's to say the Yor isn't the space ship itself, for instance?) and what sort of effects people would expect from that. If any. But setting that aside, let's pursue this line of thought and its possible game-effects for the moment.
Let's see... your computer/automation techs would let you reduce the number of crew to operate any component/equipment. You'd research various medical advances (particularly psychology and bringing down community health costs) to increase the number of people you could create as a long term crew (all that stress kicking about in space, isolated by months to years from the nearest friendly assistance or facilities), so you couldn't build a huge crew military ship at the start of the game. Humm.. So, this would work as in a tiny ship would be crewed by 1 person, small ships crewed by 3, medium by 9, etc etc etc. Ok. I'd suggest leaving the crew number limits as hard limits (although a Galactic Wonder might increase the effective number allowed at that level), so that what would happen is that in the beginning, civs couldn't build much (each component requires 1 or more people to run), but as your automation progresses, 1 crewman can "man" more components, resulting in ships becoming more capable as you advance in the game. So far so good, right?
The only real drawback to this is that it makes computer/automation techs so much more valuable as their benefits increase your ship capabilities as well as your research or construction capabilities (depending on the particulars of where automation gets placed in the tech tree).
Just my thoughts and opinions. I think using power generation is a better limitor for a game where you can play a variety of alien species.
As for the game itself, I think larger hulls should fit more onto them. That's the point of bigger hulls, to me at least. If you can fit 2 missile shooters on one of your small hulls, isn't it reasonable to expect to fit significantly more missile shooters on bigger ships? If you cannot, then what is the point of bigger hulls? If they take longer to make, but cannot do more for you, why would you ever need to build them? I don't understand the strategic importance they are meant to play otherwise.