As it is possible to create playable (and working) discarding decks for the Desctruction factions - DE and Chaos, will we see similar mechanics implemented to any of the order factions?

Before the actual Battle Pack Empire was favorable for a discard deck I think. You have cheap Questing units for Infiltrate quest and they can be better protected than destruction units. Adding the movement and control options it was and is good playable.

There was a high elf build with a hero that allowed one to look at the top few cards of a deck and pitch, a support location that forced a card pitch.

With empire though with forced march you can put all these new uber units into the quest zone and let them draw death themselves when needed and that leaves the rest of your deck open to more traditional strategies.

I've already posted a really nasty little discard deck for Order using a couple key cards. Primarily it uses the Dwarf unit that allows you to put a power token on another unit for 2 resources mixed with the Resource generating engine from the once-potent Bolt-thrower deck. You build up a huge resource pile, fend off attacks with order's damage canceling and tactic-canceling cards, mixed with recursion from Order in Chaos, and BAM! When the time is right, you wait for just before your opponent's Quest phase starts and boost his Quest unit's power to a number of cards drawn far beyond the number of cards left in his deck.

And yes, you'll need the tactic cancelers to stop him from trying to kill his Quest unit AND you may need cards to protect the Dwarf Unit you use for this (I forget the Dwarf unit's name at the moment, d'oh!). If your opponent wises up after your first match and refuses to put units into his quest, you can use Forced March to make him use a unit in his quest, regardless.

At one time it was fairly consistently hanging with the Dwarf deck. I can't say that those playtest matches were totally indicative of that particular Order Mill deck being incredibly awesome but it was very potent, that's for certain. It had the most trouble vs. Skaven/Orc rush, of course, as did BT back in the day if Orc/Skaven rush got off to TOO good of a start.