With Cho'gall's current activities and Blizzard becoming even better with phasing technology, what would you say about a 10/25 man instance that would focus Siltihus and the ressurection of C'Thun. The lore is already made, basically, Cho'gall succeded and C'Thun, far more powerful than his last form, managed to quickly spawn a huge army of Qiraji and rebuilt the Ruins of Ahn'Qiraj. Of course, the rebuilt part would be simply a wing with 5-6 bosses. You could start from a continously assaulted Cenarion Hold(a safe zone, tho,) and clean the newly spawned creations of C'Thun such as <a href="http://www.wowwiki.com/Grakkarond">a ressurected Grakkarond</a>. On certain bosses, dragonflights could help you finishing them, as lore points.
What do you guys think?