I seem to recall a Canon Video Maker of Light using the Zeiss compact lenses and saying how much better they were than the Canon EF lenses. Of course, Canon compact Cinema lenses are, like Zeiss hand assembled and tested, and use carefully selected glass to make them the best for the price. They still are not the best of the best, but much better than EF lenses, and much higher priced. Full blown cinema lenses that run 50K and way up are usually rented.
If I were a person who used a zoom lens, I'd want a par focal lens! Zooming with a ordinary Canon EF lens will put your video out of focus when you zoom unless you have a focus puller who has practiced and can focus it as you zoom. The 70D might be a solution for this, since it will maintain focus as you zoom, even on a non par focal lens like the 70-200 MK II.