Not to be too critical too early, but as a pilot very familar with SBN-IND flying, I'm not so sure a jet would be anywhere near efficient enough for this route structure.
It could be done with a Caravan like Pacific Wings utilizes, or even the C-402's Cape used on the run. I would think a B1900 would almost be overkill.
PM me, I'm interested in further information if you don't mind sharing a little.