The 5D3 is a wonderful camera....here's the dream lens line up I would consider

1. 17-40 f/4L....almost as good as the 16-35 f/2.8 for less than 1/2 the money
2. 24-70 f/2.8L II....overall awesome lens, much better than the 24-105
3. 70-200 f/2.8L II.....the version 3 converters (1.4X and 2.0X) work well here to get you 320mm and 400mm focal length respectively
4. Optional: 300mm f/2.8L II.....very expensive but totally awesome, great for indoor and outdoor sports and also works great with teleconverters to get you out to 600mm for birds and wildlife