I am not sure there is any right or wrong when hanging art. What I do know however is that it either works or it doesn’t and only your eye will tell you that. It must be visually or aesthetically pleasing to the eye.
And of course what is pleasing to the eye for one is not so for another. I personally love the order and symmetry above, however aspire to the eclectic and seemingly effortless style below.
Take time to think about the space you are working with … sometimes it is obvious which way you should head. The size, proportion and colour of frame and artwork all come into play. I find laying it all out on the floor to organise groupings first is a great start.
Lastly, a professional hanger will take the angst out of the equation … all you have to do is stand back and admire.