All I'm going to say is if they make Quan's EX rune -1 on block, that character is finished. Not only will it affect his zoning, but it will also affect his pressure as well. If his EX rune becomes -1 on block, it takes away the mind game from full screen where you have to respect rune after blocking EX rune. At -1, you could block EX rune and be guaranteed run to cover some distance.
It sucks getting knocked down with Quan. Obviously with no armor, he is helpless when he is knocked down on his back and his opponent gets free pressure/mixups.
With that being said, that's why Quan has great zoning. To make less of a chance for him to get knocked down. If they nerf Quan's zoning, I'll probably no longer use him. It's already annoying enough playing him now with no armor, I couldn't imagine playing him with no armor AND bad zoning. People will be getting in and knocking you down all the time.