The search for conventional superconductors with high transition temperatures ( \({T}_{c}\) ) has largely focused on intrinsically metallic compounds. In this work, we explore the potential of intrinsically non-metallic compounds to exhibit high- \({T}_{c}\) superconductivity under ambient pressure through carrier doping. We identify MgAlFeH6, a representative of carrier-doped transition-metal hydrides like Mg2FeH6, as a promising example with a predicted \({T}_{c}\approx 130\,{\rm{K}}\) . We propose that the average projected electron density of states (DOS), defined as the geometric mean of the total and hydrogen-projected DOS at the Fermi level, serves as a simple and computationally inexpensive indicator of high- \({T}_{c}\) behavior. Notably, the correlation between \({T}_{c}\) and the average projected DOS is stronger than that between \({T}_{c}\) and either total DOS or hydrogen-projected DOS. We also highlight the tradeoff between high- \({T}_{c}\) and dynamic stability, both of which depend on the electron DOS at the Fermi level. Our findings thus expand the pool of potential superconducting materials and offer a practical route for accelerating the discovery of superconductors suitable for real-world applications.
