Instead of using absolute values in formatting dialogues, let us define and use variables.

I often work in long documents and have dozens of styles. Using the leading for my body copy as a reference many other formatting options will use the same value or fractions or multiples of that value. Body copy might use 14 point leading with 7 points of space between paragraphs. Subheads might have an extra 7 points above. Main heads might use 21 point or 28 point leading. Bullets might use 14 points for the indent. If I need to change my leading I need to change many of those options, too.

Experimenting with different point size/leading options is complicated, discouraging tweaking and fine-tuning.

But if I could set a variable called, say “Pb” to 14 points then I could use that for leading, .5Pb for paragraph spacing, etc. Global changes to leading by changing the variable would propagate to all the other formatting options. What a time saver.