Since you have concerns about the possiblility of occasionally exceeding the SFR using a 1.0cu/ft softener I think you may want to go with a 1.5cu/ft unit. SST-60 is good stuff but probably overkill and a needless extra expense. Iron is low enough as to not be of any concern either though you will probably want to Iron-Out the brine tank a couple times a year. For grins take a look at the Fleck 7000SXT. It supports higher flow rates and is programmable to give you the salt and water efficiencies you want. You will size the PH neutralizer based on flow and the wters PH which I don't see in your post above. Again the PH neutralizer will raise your hardness so that's another reason to upsize the softener to a 1.5 cu/ft.
I posted this on another thread but it has a lot of the information you are looking for and is worth the read.