End... p2p
It probably would never happen but p2p/instancing puts a lot of limitations - it seems to me anyhow.
I think it's technically possible but there'd be issues with recent changes you'd have to find workarounds for.
It'd be similar in principle to how
git works.
Versioned changes happening on the client pushed from client to client, with perhaps the server tracking the most recent change.
That way the "overlay data" for each system would be stored network-wide on clients, and when you enter a planet's viewable "zone" the client searches the network for the most recent data overlay it can find. Ideally the data would be "light", Coriolis.io manages to get a whole bunch of ship data into a 20ish char string.
The complications would occur with many CMDRs appearing in a system across different instances and synching those instances.
You'd likely end up with a change happening, say T9 crash in instance A, but when that instance shut down the changes got overwritten by the changes in instance B which was happening at the same time and didn't get A's data. Essentially certain "branches" would win out and time would roll back for 10 minutes for select individuals. Not the end of the world and possibly a worthwhile compromise for the gains but I think it wouldn't be trivial to implement.
I guess you'd also have complications in that not a huge number of clients online, and perhaps you'd need to artificially degrade the data so it might mean wrecks don't last "forever" as they would in real life.
I dunno, it's feasible, I mean ED has lots of head-way for inter-client data transfer.