The sensitivity of an atomic spin sensor is fundamentally constrained by the quantum Fisher information (QFI) of the probe state. The pinched state, |F,0⟩, has an (F+1)-fold larger single-particle QFI for transverse-field sensing than the stretched state, |F,F⟩, corresponding to a predicted √(F+1) reduction in the spin-projection-noise-limited field uncertainty. We show that this advantage can be accessed in an rf sensing scheme by engineering a spectrum symmetric about m=0, yielding an ideal (F+1)-fold enhancement of magnetic-field response. For ⁸⁷Rb with F=2, we observe up to 2.7-fold response enhancement. Implementing this approach in a compact 0.8 cm³ anti-relaxation-coated multipass cell, we realize a single-beam, dual-axis, zero-field magnetometer, achieving 13--23~fT/√Hz over 3--100~Hz at room temperature.