How about a Bangalore Pune train starting from SBC / YPR by around 10-11 AM and travelling through Guntakal, Ballari, Gadag, Bijapur, Solapur to reach Pune by morning 6? Return also can be on the same timings. Distance in this route is just 12 kms more than via Hubli Belagavi route.
One can think of a tri weekly in the route, connecting many towns enroute.