Silicon carbide is a crystalline semiconductor with wide availability in the form of commercially produced wafers, due to it's application in the power electronics industry. Silicon carbide has many properties that make it an ideal platform for quantum information science, in particular it is a host to many optically-active spin defects that can be used as qubits. These optically active spin qubits may be used for quantum computing, communication, and sensing, by leveraging silicon carbide's wide electronic band gap, low abundance of nuclear spins, optical transparency, and mature fabrication techniques. Optically active spins in solids consist of crystal point defects, with an electronic or nuclear spin degree of freedom that can be driven by magnetic resonance, and optical transitions that can be used for spin initialization and readout. However, interactions with the surrounding silicon carbide lattice has an influence on qubit operating conditions, control schemes, and host material engineering. Interactions with phonons, spins, charges, strain, and electric and magnetic fields can cause relaxation and decoherence of the qubit's state. However, such interactions can also be used to drive transitions and engineer resonance conditions in the system. This thesis explores how we can use such interactions as a tuning knob for quantum science and technology applications, while minimizing their detrimental effect on quantum states. This thesis focuses on the study of two defects in silicon carbide, the vanadium impurity and the divacancy. Using all-optical methods, we studied the spin-relaxation processes of vanadium at milikelvin temperatures and observed a temperature dependent contribution of the direct or Orbach phonon relaxation processes between 50-1900mK. Furthermore, we characterized the orbital strain susceptibility and predicted the spin-strain susceptibility of the vanadium defect. On the other hand, the divacancy is a well characterized spin defect that can be used to benchmark silicon carbide material environments. We compared the spin $T_2$, and $T_2^*$ of divacancy defect ensembles in thin films and bulk wafers to benchmark and optimize a novel silicon carbide spalling process.