OT: my opinion:
I just don't see how you could do anything further. All organized pve content still requires actually zoning into the instance. Which I think is a very good requirement. (Flex won't be queueable in WoD. Only reason it is now I believe is it was easier to implement with new flex tech).
You can't really force people in LFD to sit in front of an instance for the queue to pop as the audience LFD is designed for doesn't have much time and LFD lets people multi-task.
Discovering all instances like Cata could work for max level dungeons (not for leveling ones as the Alliance and Horde are starting in opposite areas) where you can't queue up (biggest practical reason Cata's didn't work, people just black listed certain ones) for any until you discover all of them (completing this would be account wide) I wouldn't mind this at all, but overall reaction wouldn't be great.