One of the things that Burning Crusade did right that every other MMO other needs to copy is quest progression.
I’m not talking about a good spread of quests in each zone to cover the appropriate levels. I am referring to quests leading from one quest hub to another. In Burning Crusade you will get 4-5 quests in the first place you get to in the zone. Most of these quests will be completed in the same general area and 1 or two of those will lead you to another small quest hub with 4-5 quests of its own. Finishing all of those quests will net you another quest to go to yet another hub. And finally you will get a quest to go to the next zone where the steps will repeat.
That type of design just makes it feel like you are always moving forward and seeing new content while leveling, and it gives you a good idea of where you should be going for your level. If you first go to Outland and you don’t have a quest to go the Blade’s Edge Mountain, you should probably not be there.
This also allows you to tell better stories with the quests, since players will all be progressing down the line. Unless they decide to just grind through mobs.
What I find most amusing about Quest Progression is when you go back to Azeroth and level an alt through vanilla WoW content. It shows a huge difference. In Duskwood you get all of the quests in Darkshire and then you make huge cirlces around the zone filling the quests out with tons of traveling, watching the scenery go by. Then you move on to the new content in Duskwallow Marsh and you go from quest node to quest node and bam you gain levels in about an hour and a half of playing.
Of course then you wish they would redesign of the old world to match the new quest construction.
