True agency in the isekai warrior archetype is inversely proportional to systemic optimization. While a YPS-4 rating suggests a dominant presence, the disparity between a Nation-level combatant and a City-level warrior reveals a fundamental divide in how power is acquired. Asuna functions as a peak expression of a virtual system; her efficiency as a guild commander stems from her ability to internalize and exploit the rules of Aincrad. However, her Ego score of 0 exposes a reliance on the framework provided to her. In contrast, Eris operates at YPS-3, a lower destructive ceiling, but her growth is a deliberate act of rebellion. By abandoning her noble lineage and leaving the protagonist to undergo years of grueling training, she transforms her weakness into a weapon through sheer volition. Asuna is the master of the environment, but Eris is the master of herself. The YPS gap is a distraction; the real story is that the character with less raw output possesses more autonomy. Asuna's power is a result of adaptation, while Eris's power is a result of conquest over her own nature. This comparison proves that a higher YPS tier often masks a lack of self-determination when that power is granted by the world's logic rather than carved out of it.