Thanks to everyone for their input. I got the 5D3 with the 24-105 and I've been happy with it that lens thus far. I've also acquired by brother's 50 1.4, swapping it for my Sigma 30 since he has a 60D. I also retained the Tamron 70-300 VC. I purchased it awhile ago because I wanted to cover that focal range, though I rarely shoot long. Nice lens for the price, and seems fine for my hobbyist usage. Future upgrade to that would dependent on a need for something faster. I've decided that I am going to replace the 50 with the 35L and I just got a good deal on the 85L. It's absolutely an extravagance, and I did not intend to end up with one, but fell in love with it after playing with it for a few hours. The 35L, 85L, and 24-105L will be my core lineup, with a Tokina 16-28 coming at some point for when I want to shoot ultra wide.
Thanks again to everyone who contributed. I'm finding the 5D3 and these lenses to be a joy to use. I'm only a hobbyist, and my gear is far more than I need, but I just love these tools.