i think you should get a 50mm 1.4 first and it should probably serve you very well for walk-around.
You probably wouldn't want to take out a $1000+ lens, just to walk around and put it in your backpack. You probably want to use a $1000+ lens for projects and specific assignment.
That's just my opinion.
85L II is better overall, better sharpness, better built, better focus accuracy(no focus shift stuff happen ever.).
However, people still love 50L, for those who think this is the only focal length they use 90% of the time, or this is the focal length they feel most important to them, or they have abundant cash.
I prefer 85L and get a 50mm 1.4, just because 50mm is also a walk-around focal length for me.
If I did all my work in 50mm range, I would consider 50L regardless of its price.