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The original topic was about emergent gameplay. Let players "direct the plot".
You can have that without impacting the solo player much as long as you provide things for him to do. Those who want the "drama", competition, ... etc., they can go ahead and have their "clan wars". Those who don't can, as you mentioned, do 5-mans, LFR, level alts, ... etc.
The problem with WoW is players have next to no control over how things play out - apart from clear raid, don't clear raid.