A couple ideas were suggested
-The Alliance get thrown out of the city. The problem is that it would really suck for the Alliance if that happens.
-The Alliance leaves the city volontereely right after the siege. Way to look like a loser in front of your ennemy faction.
-The Alliance keeps a military presence in Orgrimmar but that would be really annoying for Horde players.
-Orgrimmar is destroyed and Bilgewater Harbor is the new capital. Would new to redo two zones and some Alliance players would whine even if it would be the greatest victory for the Alliance.
None of theses would really work so here's my idea: taking hostages. The Alliance would leave the city with hostages willingly given by the Horde. This would guarantee the Horde wouldn't become super hostile again and peace would be brought back between factions. No need for a lot of hostages, only one or two per race could be good. Maybe none for some races.
It could also create problems with the alliance as some would want their head while others would befriend them. The Horde wouldn't really have any reason to be against that as good treatement would be guaranteed and peace would be back.
Here are some possible hostages. Could also be no-names but having one or two big names could be interesting.
-Eitrigg. Being friend with Tirion and old, Eitrigg could volonteer and go learn more about paladins and other culture.
-The Grimtotem friend of Baine in The Shattering
-Lord Saltheril, the party loving lord in Eversong Woods.
-(SPOILER) That troll druid the Alliance saves in 5.3 (SPOILER)
Just an idea I had.