Here, we explore the effect of copolymer chemistry on the phase behavior and viscoelasticity of complex coacervates. To this end, we utilized a library of methacrylate copolymers with varying charge densities and hydrophobicity. Our results show that changing the charge density and hydrophobicity drastically affects the phase behavior─with charge density dictating the salt stability and hydrophobicity controlling the polymer concentration of the coacervates. Small-amplitude oscillatory shear measurements were used to study the viscoelastic response of the coacervates, leveraging knowledge of the coacervate phase behavior in tandem with time-salt superposition to construct a series of time-salt-copolymer master curves that highlight the effects of polymer charge density and hydrophobicity. These combined data show evidence of charge-dominated and hydrophobicity-dominated regimes, allowing for an understanding of how copolymer chemistry can be used to tune the mechanical properties of complex coacervates.