I guess it depends on a number of factors.

Sunrise/set....at last light I dont want the sun directly on me...plus it leaves shadows if
the deer pass behind you
skyline.....are you hunting a ridge? Stay below the ridge top.
background...what kind of cammo/cover is behind your setup....again human outline

Personally my favorite stand location I set up with the trail in front 20-40 yds L-R
and behind me R-L...less chance of a spook IMO. I like using the trunk as cover so I'd rather set up with the deer
coming from behind me or to from my L-R. I use a climber so I dont have the branches to act as
cover as you would with ladder sticks or fixed stand. Good hunting.