Scaling Back Memory Parameters

We have a sizeable RAC production DB that gets heavy usage.  Occasionally we clone this back to single instance development DBs that don't see as much traffic.  We have several of these single instances on one host.  Since they are not used as heavily, we definitely don't need the same memory parameters from the RAC version that would normally come over as part of the clone process.  LSS (long story short), what's the best place to start when shrinking down these parms?  I know several are derived or help derive other parms.  We want the end result to be a single instance that has enough memory