The high-throughput exploration and detailed chemical and structural analysis reveal the profound roles of spacer cations in making quasi-2D HPs. Among them, BDA homogenizes the vertical phase distribution while compromising phase stability, whereas PEA offers a flattened HP surface with excellent phase stability at the expense of vertical phase inhomogeneity. Considering these features, it is reasonable that employing both spacer cations to quasi-2D HPs can synergistically allow us to exploit the advantages of each component while compensating for the drawbacks.