Re: If the Reds do convert Chapman...
If they pulled the trigger and put Aroldis in the rotation, I'd guess that Leake would get optioned (as they still need depth), and that they'd attempt to sign a closer (Madson or Broxton most likely). If they failed to sign one, then they'd go with an in-house closer (LeCure, Hoover & Marshall are the most likely candidates IMO...I'd lead towards Marshall)
And yes, I'm in favor of doing this too.
Pitching and defense...anything else is gravy. Mmmm...gravy.