In my life I’ve seen interesting discussions about which JRPGs have the best protagonists and which ones have the best non-protagonist party members but I don’t think I’ve seen this one.
Since “best” can mean anything subjective let us know what it means in your case! i.e some might choose a party based on the writing+design of the characters, others might focus on their character arcs and themes, or on the overall diversity of the party (full human teens party vs diverse ages or diverse species vs whatever Chrono Cross has going on, etc).
Final Fantasy 15 has a great core party. They all have a relation to each other and a lot of the game is focused on banter between them. They feel really natural in a way. It’s definitely the best aspect of the whole game. Each of the support characters has a DLC episode just about them and there is even a short anime with additional backstory for them. I don’t think I’d rank them in my top 5 individually (although Ignis comes close) they are the best overall team.