I think kitchen knifes are like good food. Every thing is just as important, every thing has to come together just right for the perfect blade. How ever a good blade can be achieved by over compensating for some shortcomings.
So not necessarily in order:
Good recipe= geometry
Is it cooked right= heat treat
Ingredients = steel
How does it look = well looks, this includes the handle.
Does it taste good = how does it cut?
So based on that I would say heat treat is #1. if the blade's not cooked right it will suck.
# 3 hoe it cuts
#5 the steel.