Musical scores are frequently annotated with harmonic information, but widely used text-based methods rely on a limited number of visual channels. Though glyph-based methods exploit more channels, existing systems often violate perceptual design principles when employing color and rarely capture the frequency of chordal changes or their harmonic function. In this work, we introduce a new design idiom for augmenting sheet music through chordal glyphs embedded directly within musical staves. Harmonic concepts, weighted by saliency and categorized by data type, are mapped to visual channels ranked by discriminability. Preattentive processing is leveraged to support various user tasks, alongside redundant encodings of foundational harmonic elements to improve overall perceptual effectiveness. Key names and chord roots are displayed using parallel hue-based 12-step categorical colormaps. We then distill several design implications inherent in assigning colors to musical pitches regarding perceptual and linguistic effectiveness. Following this discussion, we outline open research directions.