Originally Posted by
Heladane
The optimal path seems to be:
20-58
Sequentially quest the zones (as Alliance) Loch Modan, Westfall, Redridge, Darkshore and Bloodmyst Isle - These are all "starter" questing zones with tightly packed together easy quests which have you generally doing very little for quest completion.
At the same time you should exclusively queue for Ragefire Chasm and Stormwind Stockades. These are two of the quickest completed dungeons and the completion xp alone is a solid addition to your leveling. If you are a leveling healer or tanking class this will be a sizable portion of your leveling, and you'll be getting to know these two instances well.
58-73
Do either Northrend or Burning Crusade questing while queuing for both Utgarde Keep, Ramparts and Blood Furnace.
74-81
This is the rocket fuel segment of your leveling. Switch your settings to do heroic dungeons, and go and sequentially solo every single Burning Crusade Heroic Dungeon. They give outstanding xp/gold and you will be one-shotting your way through the dungeons.
81-82
Most of the Heroic Burning Crusade Dungeons will stop giving you xp at this point, so go and do some of the raids. Serpentshire Cavern has level 72 10 mob pulls which you can AoE in seconds and give massive amounts of xp.
83-87
Unfortunately this is back to questing and queuing yourself for dungeons. These levels can seem like a bit of a grind after coming off the rocket fuel of 74-82. At 84-87 you can solo heroic Northrend dunegons, but I'm unconvinced that this is faster xp than questing. It is however a very good moneymaker.
88-90
Heroic Zul'Gurub is your friend. Solo the dungeon in a big circle avoiding all the bosses and killing all mini-bosses. Get back to the start, exit, reset, and do again. 5 circles and resets should be enough xp to go from 88-90.
90-110
Exactly the same as prior to 7.3.5
All of the above is obviously class and spec dependent in terms of how easy it is to do. Certainly if your class has a tanking spec or healing spec, particularly a tanking spec, you'll see a lot of the insides of stockades and ragefire the first 40 or so levels, but blast through the completion xp.
Whether the above is fun is a different question entirely.