I have a 5DIII body with the following glass:
16-35 2.8L, 24-105L, 70-200 F4 IS, 50 1.2L, 100 2.8L Macro
All very nice lenses. I am not using the 50 quite as much as I thought I would, I could suck it up and just say "learn to use it more you idiot". But there's a nagging feeling there I could sell the 50, 24-105, and 70-200 and pick up a 70-200 2.8 II, and the 24-70 2.8 II for a difference of just under $1500 and wind up with 4 exceptional lenses.
Worth it? Or stick with what I have?
I am mostly a walk around guy, cityscapes, landscapes, but I also do some photography in dark places like in night clubs, hence the desire for fast glass.
. I'd also keep the 24-105 as a walk around lens. Just my 2 cents 

