I've done all of my adjustments in 1/8 turn increments starting from full soft.
For the most part, I did the same setting all around while driving all over the west coast.
On occasion there were some weird oscillations, and I firmed up the settings on that end. Then drove over those same sections again, changed the setting, and tested again.
Though in the end, it's all subjective. Go with what you are comfortable with.