Sheetrock Over Foundation Insulation
Before applying sheetrock over foundation insulation–be it foam board or studs–apply a layer of 7/16″ OSB. It’s relatively inexpensive, and provides nailing for shelves, pegboard, tool hangers, etc. over the entire wall. If multiple nails or screws are needed for a heavy item, there’s plenty of nailing for that to.
This can also provide extra support for kitchen cabinets, at the cost of about 1/2″ interior space.