I have found that the massive wreckages near the center are actually station wreckages that contain LARGE quantities (sometimes millions) of resources and also sometimes goods. If you select the pieces of the wreck, most of them will show no resource count, but they can still be salvaged normally. Look for core blocks like generators, etc. as they give the most resources and money when salvaged. Typically, one piece of the wreck can be selected and it will show the resource count and any goods in its cargo holds. I'm pretty sure this is a bug where the one 'chunk' of the wreckage displays the resource counts for ALL of that station's wreckage chunks (it seems to mostly effect stations). However, the blocks that show resource counts are the only chunks that will actually contain cargo (from what I have experienced) so I typically find and focus on those. Resource counts are visible from 5km away, but you have to be within 0.5km to see any cargo on board. Cargo salvaged from these wrecks isn't considered stolen, so its pretty much free money laying about in space. Being that these are stations, they typically have a LOT of cargo and they can quickly fill your cargo hold!
Also in this region are Resistance Outposts, which are part of the main quest line to defeat the end boss. These outposts are typically closer to the center than any other faction stations and I have seen an instance where one spawned as a turret factory. Due to its proximity to the core, the turret factory had a high tech level and therefore produced some VERY powerful Avorion turrets.
My impressions of this area is that we are experiencing the aftermath of the Xsotan invasion and the wrecks are the remains of the factions that once inhabited these areas. After conquering the area, the Xsotan set up their breeder farms. I remember hearing somewhere in the story that the Xsotan consumed everything as they went, which is why the breeders look like asteroids. The asteroids (and everything else) are being consumed to produce new Xsotan ships. I wouldn't be surprised to see missions to destroy breeders or special loot or resources that can drop in the future as the game continues being developed.
Some Screenshots:
No resources shown:
All the resources and cargo:
MANY resources:
Salvaging resources, even though it says there are none: