What are measurements for the whole nose to usually go by?
The nose can be measured using many variables and ratios comparing length of dorsal line to tip projection to name one. These "standards" were based upon classic measurements in greco-roman figures. Obviously this does not mean much to the billions of people not of this origin!
There is actually no average length which can be measured in numbers because what we always consider is aesthetic proportions. Ideally, length from the tip to the base of the columella should be equal to the vertical length of your upper lip (the distance between the base of your columella to your upper vermillion border.