Well I guess I don't understand either. Based on Solarius response to my last post above in this thread, this now seems to be possible:
So, I've been wondering (Hard.) about making a taller X-Com base map by adding a surface level to the underground level. Basically, adding one layer of earth above each facility, and above that place some appropriate buildings stolen from Hobbes' military installation (for example, a closed dome above each defence, a recreational area above Living Quarters, a big hatch above each Hangar, etc.). It would allow us to fight aliens on the ground before retreating underground for a second stage, if need be.
Now, the problem is, these would require many new tiles for the surface. I wonder how one would handle that... I don't really have any experience with such tricks. Guys, what do you think?
But with a two layer system where above ground is an independent facility from the below ground facility directly under it, the player could put the living quarters under the closed dome and the missile defense under the recreational area! Also, if a surface facility gets destroyed in a base defense, it wouldn't make sense that any other surface facilities would be lost due to being disconnected from the rest of the base. If an underground facility is destroyed does that have any effect on the surface facility directly above it? Also what function or service would a giant hatch provide if a hanger was never built below it? Or if the hatch wasn't directly over the hanger?
I was thinking for example something like the early base has an above ground barracks for staff and an above ground anti aircraft artillery gun for defence. The player through research then unlocks living quarters and missile silo. The player can now upgrade or replace his barracks facility with the recreational area that has living quarters below it. Similarily, he can replace the triple-A gun with the underground missile silo which has the closed dome on the surface. Thus, the above ground portion and the below ground portion are part of the same facility. I realize that post I quoted is almost 5 years old and his vision may be quite different now.
So like I said, I don't understand. Various people in this thread want different things. Players can easily make small text only mods that give them more living, storage space, or whatever so that they wouldn't have to build more than one facility to meet those needs and thus have plenty of remaining available space for facilities in their bases. Modders want to expand the game's capabilities so that they can add cool new content like bases with both above and below ground structures that is different from what others have done. And devs don't want additions to the code that they feel are unnecessary especially when viable alternatives exist.
As for bases that are variable in the x, y, and z axis for facility count, or number of bases, or location of bases on land, on sea, on seafloor, on clouds, moving, in orbit, on the moon or whatever, I feel that it would be better if that was under the modders' control so long as there aren't negative impacts to existing mods. But underappreciated devs have better uses for their time.