I don't know why they did away with the old ICC-style incremental buff. That buff is what kept guilds able to keep raiding that place for a whole fucking year. Guilds that were progressing on Heroic Putricide in June (after ICC release in December the previous year) most certainly would have collapsed without that 30% buff to help push things along.

As far as the out-of-raid game goes, they could do a whole lot. Blizzard could implement nearly any multiplayer gametype from any game in the form of an instanced zone.

• Wave-based PvE multiplayer, like Mass Effect 3 or Gears of War. Build maps around the Proving Grounds concept, and have it done in 5 man groups.

• MOBA style 5 on 5 PvP. Not isometric of course. 3 lanes, towers, a jungle, the whole deal.

• Rip off the entire Smite arena concept, because it would suit WoW perfectly. Let players choose if they must be grouped with guardian/support on the queue screen, that way people can get 5 DPS insta queues if they want.

• A pure TDM battleground, to give players who just want to PvP without caring about capping objectives a place to do it. Not as giant as Tarren Mill/Southshore, maybe 15 on 15. Spread poweups around the zone to get the groups to split.

• Garrison follower combat, turn based RTS style. Have missions where you pick three followers and you as their General get a top down view and can control where they go and what they do. They made plants vs zombies, they can do this.

• "Gyms" and "Leaders" and "Leagues" for Pet Battles. Let's not pretend it's not Pokemon. Leaderboards, "badges," beating the finest five instead of the elite four or whatever. Challenge players, who earn ranks, through a global Pet Battle window instead of only random queues. Make a structured form of competition with Pet Battles instead of just something that's out there with nothing supporting it.