IMO if IR runs one dedicated daily train from Rameshwaram to Shirdi Via Trichy-Chennai-Renigunta-Gadag-Daund would be best due to several reasons
1} First ever End to End Connectivity for piligrims
2} First Day time intercity between RMM to Chennai
3} Reduces load on Haripriya which is highly waitinglisted
4}...
more... First ever day connectivity between BAY and BJP
5} Connecting key parts of TN and KA
Route might be 350 km long but patronage will be awesome
Timings as per my opinion should be
RMM 05:00
MS 18:15
RU. 21:10
BJP. 11:15
SNSI. 20:15