In my opinion, railways could start a new Rajdhani from SBC to NDLS via Hubli, Miraj, Pune, Vasai to NDLS.
Can leave SBC at 22:00 PM , Hubballi at 03:30 AM , Dharward at 03:55 AM , Belgavi at 05:35 AM , Miraj at 07:30 AM , Pune at 11:55 AM , Panvel at 14:45 PM , vasai at 16:00 PM , to reach NDLS at 07:00 AM and return with the same time with PM at SWR/SBC
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In that case it covers interior KA with NDLS with fastest Rajdhani connection and make sense for calling Karnataka Rajdhani