Lead-free perovskites are increasingly regarded as sustainable alternatives to lead-halide counterparts, addressing pressing concerns of toxicity and long-term device reliability. To provide a holistic framework for material evaluation, a performance figure of merit (PFoM), defined as PFoM = (Efficiency × Stability) / Toxicity Index, is applied to representative lead-free perovskite systems. Recent literature data are used to calculate PFoM values for tin-, bismuth-, and antimony-based compounds, with the trade-offs between efficiency, operational stability, and toxicity visualized through heatmaps and scatter plots. The results reveal that while tin-based perovskites demonstrate comparatively high efficiencies, their stability remains limited; conversely, bismuth- and antimony-based compounds exhibit superior environmental stability and low toxicity, though at the expense of efficiency. Importantly, device-engineering approaches—including two-dimensional/three-dimensional hybrid architectures, incorporation of metal–organic frameworks (UiO-66), SnF₂ additives, and NiOₓ transport layers—have been shown to substantially improve both efficiency and stability, thereby enhancing overall PFoM rankings. These results highlight the promise for reliable, effective, and environmentally friendly perovskite photovoltaics with thoughtful material selection and creative architecture.