I'd also go with a 24-70/2.8L II or get the Tamron 24-70 2.8VC.
I really liked the Tamron, but, ended up with the 24-70/2.8L II because I could afford it at the time and because the Canon was slightly better optically and focuses slightly faster.
Otherwise, I'd get a 24-105L and use it stopped down (i.e., with flash).
When working with primes, I love to have two bodies so I can have both 35L and 85L at the ready. Otherwise a 24-70 with a flash is usually good enough.

