The SWTOR have implemented public zone instances, it was avaialble in beta to switch instances (for example - coruscant 1, coruscant 2, etc).
So, add more physical servers to the clusters for each shard, make the instancing avaiable as it was in beta, increase the cap.
It actually IS that easy.
EDIT: And yes, the only problem is EA cutting the costs, since we already paid for the incredibly expensive CE of the game. GJ!