The two best lenses for your camera/situation would be without doubt the Canon 24-70 f/2.8 and the 70-200 f/2.8.
If you want IS lens, substitute the 24-70 for the Canon EF 24-105mm f4 L IS USM Lens.
If you're shooting "tethered" from a tripod, then go for the cheaper non stabalised version
Expensive, very, but they're the best you can get.
A good place to get them is "Flash Cameras" not what I would call an ideal trading name, but this is the company name of the most respected Ian Kerso.
[email protected].
Don't let the fact that he's an Ebay trader put you off, I've bought several items for my 7D of him this year.
Canon 70-200MM 2.8 IS LENS £1,239.00 (Ebay), but less if you deal direct.
(£1500 at Warehouse express)
Type Kerso in your search bar for reviews of this company.
Harry