Surface-enhanced Raman spectroscopy (SERS) offers chemically specific optical readout for exhaled volatile compounds, reactive gases, respiratory aerosols, and condensate-associated biomarkers. Breath analysis, however, is controlled not only by the lowest detection threshold but also by transport through humid air, selective retention at the enhancing surface, near-field accessibility, sampling hardware, and spectral decision quality. This paper asks which SERS breath-sensor architectures retain analytical credibility when the complete route from exhaled target to interpretable Raman signal is evaluated as a coupled chemical-transfer problem. A twenty-eight-entry analytical matrix was organized by target phase, recognition or capture layer, enhancement geometry, breath-contact mode, measurement descriptor, and uncertainty status. The resulting method, Transport-Coupled Sensor Stratification (TCSS), evaluates each architecture through seven criteria: threshold strength, selector chemistry, hot-spot/capture architecture, breath-system integration, learning support, breath-target alignment, and uncertainty control. The analysis identifies the T-Si/Al\textsubscript{2}O\textsubscript{3}/Ag/Au light-trapping substrate, the vapor-generation paper-based thin-film microextraction system containing Au nanorods, quantum dots, and NU-901, and the Ag/Si/Ag micropyramid substrate as the strongest sensitivity-mechanism candidates. Deployment-oriented selection gives a different ordering: the Ag nanocube breathalyzer, hollow ZIF-8/gold-superparticle breathing-valve sensor, Au–TiO\textsubscript{2} nanocomposite, and TiO\textsubscript{2}-supported Au platforms gain importance because they connect sensing chemistry with breath handling or biomolecular readout. The study concludes that no single SERS substrate is universally optimal for breath testing. Credible selection depends on matching analyte phase, capture chemistry, plasmonic geometry, breath-interface design, and validation status to the intended target class.