That doesn't serve much of a purpose. It will, instead, shrink the talent pool, to include average passengers from strong teams ahead of talented players from lower-league stragglers. The current 15-12 format is fine as it is, but they could do well to invite foreign players to the event, and also a foreign team to the Duleep Trophy. If it wasn't for their discovery of Dhoni, who carried a weak team repeatedly and won for them, they'd be stuck with Parthiv Patel or Dinesh Karthik, both weak links for whom the team needed to adjust a lot, and India would lose Rahul Dravid five years earlier.
A whole lot of internationals who are idle can fill in for the India stars away on national duty, often the bane of Indian domestic cricket. That will strengthen the standard of the game, although it will take time. These players should be full-fledged members of the teams, like the system in England.
The Duleep Trophy and Deodhar Trophy should be played when there is no international action, like the IPL.