Ever rerolled all your items into Crit chance% + Crit power, felt good about how the results are going to be - yet always been left wondering what exactly you just did? You, me, and everyone else.
My suggestion; a quick stat overview of your character somewhere to see the cumulative properties you have, a simple visual breakdown of your stamina, crit, resistances, LIFE? knowing how much life i actually have would be pretty useful in planning my loadout. Etc
TL;DR, Character stat value window for easy optimization (and just plain curiosity quelling)