Leveling Speed Multiboxing

[Apatheist]

If you're 2boxing it will be faster just to quest and grind a few mobs in between. Even collection quests won't be too bad with only two characters.

Your lives would be made a lot easier by adding a healer though. Warrior/mage and warrior/warlock are kind of awkward pairings that don't compliment each other very well. Both the mage and the warlock would level faster solo and warriors are slow to level without a healer.

In fact, it'd be much faster to level the mage solo and then use it to dungeon boost the warrior once you're 60.