Every time the topic of tuning a guitar pops up, I feel a necessity to point to how Eric Johnson tunes his.
He tunes the G string perfectly on pitch, and tunes every other string by playing G’s using the open G as a reference (3dr fret on the low E, 10th on the A etc). It’s brilliant to do it this way because by doing so, you compensate for small imperfections of the intonation caused by imperfect (no such thing as perfection) saddle adjustment, action height, fret wear etc…