It's not what is in the lens, but what is in your mind! There are no boring lenses! There are boring minds.
The 24-70 is 3 1/2 primes, a 24, a 35, a 50 and ...at 70, almost an 85... and the Mark II has the IQ.
Now we all know that you can buy primes in the f1.4 range for all these focal lengths. What you buy is shallow depth of field. Yeah, I 've shot my share of shallow DOF, but it does get boring after a while. I am sick and tired of portraits consisting of a pair of sharp eyelashes shot at f1.2 and a fuzzy nose and hint of ears. If that's your thing, ok. It's not mine and yes, it is sooo boring.
Once we get to f5.6, I'd take the 24-70 MkII any day of the week and for any composition. That's my thing.
Buy the lenses that fit your thing, what you shoot and what you aspire to accomplish.