The Canon 7D like most DSLR’s has a dynamic range of around 5 to 6 stops, you will start to get into trouble if your scene exceeds this range. The camera sensor and metering system is set up to be a little flat, because preserving highlights is the priority of the meter, once the highlights are blown there is zero information left.
I don’t think it is viable with the 7D to go past iso 1600. I have set my 7D up with a preset for general shooting and another for 60fps. I used a set up that is making the rounds online, from Tyler Ginter, he has a tutorial at vimeo #7622493
With these presets you will have to do a little levels adjustment and maybe some color grading, I do find a slight magenta cast on 7D files.