Fellowships are easily formed, and every class has a well-defined role to play: Guardians are damage-absorbing tanks, Minstrels heal, Lore-masters cast spells and send animal familiars into the fray, and so on. While each archetype can survive well enough on its own, thanks to expanding libraries of interrelated skills, there's another compelling reason to join up once you hit level 12: powerful Fellowship Maneuvers that deal tremendous damage, or restore power and morale. Finally, a tangible new reason to group beyond hollow designer mandates.
You'll still run into your identically-equipped twin too often, but such distractions seldom break the illusion. In fact, one could argue there are more opportunities for character customization than elsewhere, thanks to the Deed system. Make it to level five or eleven without dying, or kill a whole mess of goblins, and you might earn a title. Kill yet more, go on a sight-seeing tour of the region's ruins, or fulfill some other unexpected condition, and you'll earn "traits" with which to fill the slots that each level opens, improving your effectiveness. The familiar ritual of skill-invoking combat is addictive enough, but this intoxicating addition puts your brain on a virtual dopamine drip. Add in the ability to take a break from your hero and slaughter fellow adventurers as a level 50 monster, earning "destiny points" to spend on upgrades, and you might never leave the house again.