"Everything you need. Nothing you don't."
Ummm..Cajun...that gun needs either better stocks or a Tyler T-Grip, either a night sight or gold bead, and chamfered charge holes. A trigger job is optional, but I prefer to have them performed on the gun. In my opinion, these features are the minimum changes required for a self-defense revolver.
I think the OP will find a gun with 3" barrel to be a good compromise for carry. A four inch barrel will work just fine though.