Taking into account the effects of atomic number of M in superalkali unit and pore size of graphyne on first hyperpolarizabilities, we conclude that the combination of superalkali OLi₃ and GTY with a large pore is more advantageous for designing superalkali salts of graphynes with high stability and excellent NLO properties. Besides, the large β ₀ value of OLi₃⁺@GTY^– is a new record for superalkali/superalkaline-earth doped graphynes. The above results may provide important references for further studies of such graphynes and their derivatives.