I look for a cleansing value BELOW the low end on the recommended level on
lye calculators.
I personally find that any cleansing value above 11 or so is drying to my skin.
Your reaction to the soap may simply be that you are taking too much of the natural oils off.
If you raise the SF without lowering the cleansing value you will be leaving surface oils from the soap on skin stripped of it's natural oils. Still "dry feeling". If you lower the cleansing value and leave the SF alone you will not be stripping as much oil from the skin.