I wouldn't pigeonhole myself into being a prime only guy. I found myself in a very similar situation as you. Most of my shots with the 24-70 were usually at 3 different lengths, 35, 50, or 70. If they were at 70 it was because the lens wouldn't go longer. So I bought the 35L and 85L but I still use my 24-70 regularly. I am still debating what 50mm I want to get. I'm on the fence between the 50L and the Sigma.


I use the 24-70 for product and food shots because of it's MFD and higher magnification. I also use it for events and photojournalist type work where I can't get to the exact spot I want.


Just a side note; I think the ISO Charts on this site are a good starting point in evaluating a lens, but they don't tell you much about real world performance. I know for certain the 85L ISO Chart doesn't tell you anything about how amazing that lens is. I have a feeling the 24L might be better than the ISO charts lead on.