Switching from Canon 7D to FF (advice needed)

Go dual.

Keep your 7D and 70-200 for sports perhaps portrait too and sell the other two lens to buy a D600 and a 85mm 1.8g.  That 70-200 on a 7D is still formidable with good light.   Besides I hear that new 24-70 II L is wicked,  2300 bucks though..  Ouch!

The L Lens to Canon is like Exmor sensor to Nikon.