Chennai-Mumbai route is already criticized for being a slow route. Trains running through alternative routes via-SWR will be more slower, making them unattractive for end-to-end passengers. Connections to Mumbai for interior Karnataka can be provided from SBC or MYS( As SBC also requires more dedicated connections to Mumbai). For BAY and UBL, SR has floated proposals to increase the frequency of MAS-Vasco, but was turned by SWR multiple times. It is SWR's responsibility to provide dedicated connections to MAS for BAY/BJP etc. Chennai division will be more concerned about the connection to Mumbai/Pune/Vasco than the intermediate stations in other zones. As of now, the shortest route via Guntakal ( not Gundakkal, just correcting) should be sped up first, before focusing on alternative routes between MAS-Mumbai.