>>1749142
Eh, why not. Some other old men not mentioned are Ahab, Amatsumara, Arsalan, Daikoku, Itzamna, Qinglong and Tianzun. You could make an argument that a few of them are more around middle age though.
And coming up with more actual grandpas is still kinda tough. Azathoth could be since some other Old Ones have spawn of their own, and maybe Himavat too but that's under the unlikely assumption his daughter ever managed to have sex with Shiva.