Basically, the old island structure class wasn't up to what I required, so it's been ripped out & replaced with the concept of a 'structure cell'. These replace the old single structure, providing a generic mounting point for a small complex of structures and objects all working towards a single purpose. Damaging any 'working object' in the cell will reduce the efficiency of the cell's work (e.g. object production / raw material extraction). Also makes the islands look better as well as being more flexible for procedural sub-structure and related object placement.
Structures with a view:
Manta employing the new bomblet pod:
Now I'm off for my summer hols after that hackage workout - cya in a few weeks :P
P.S. Hope you notice the todo list up there is actually shrinking... :)