I'm in much support of the 35/1.4 and 85-100/1.8-2.0 combo. From my experience quality of the final image will be stunning, as well as the wallet won't be hit that hard. It gives you a nice flexibility to work with variety of lighting conditions, forces you to go away from the zoom mentality (better compositions). It is by far the best compromise and if you are still itching for a 50mm, you can always pick up a used, sharp copy under $100.
On my 6d my favourite go to lens in order are 35 1.4 (Rokinon), EF 50 1.8, 70-200 2.8 IS. My normal length 24-70 just sits around gathering dust being only used as a backup.
Of course this is just my opinion and I am in no position to say that 24-70 is a bad lens but I find that my favourite images more often than not come from the primes. Just 2 c.