Type Ia Supernovae (SNe Ia) are useful as cosmological rulers due to their standardizability. However, there are still open questions that may be important for reducing systematic error in the Hubble residual. My Ph.D. focused on using the spectrophotometric SNfactory dataset (Aldering et al., 2002, SPIE) to classify SNe Ia based on their color-magnitude (CMAGIC) diagrams (Wang et al., 2003). I have defined a new parameter to describe an empirical feature on the CMAGIC diagram, called the “bump” feature, and found a significant correlation between the size of this feature and the slope of the first linear region of the CMAGIC diagram. This relationship may reflect physical processes at the photosphere, namely, the inhomogeneity of Rayleigh-Taylor instabilities (Aldoroty et al., 2023a).