That's good for discussions, but practically, doesn't look likely. Any reduction of coaches/quota from SBC in the ONT's will be very problematic. As it is, just the diversion of the ONT via Nelamangla was not welcomed by passengers on the Mysore route. Now if half the train is diverted/extended to GR/BIDR, there will be a lot of backlash from SBC/MYS passengers.
These half-baked solutions will not work. Only lifting the restrictions on either the Braganza or Shiradi routes will solve these problems.