Baptism scene symbolism

As we know the baptism scene is one of the most iconic scenes in the story. It’s kind of like the “changing of the guard” for the Corleone family. Obviously the major changed is Mike establishing himself as the most powerful and ruthless mobster in the country. However also the men carrying out the orders are the new regimes besides Ckemenza of course. The past you had Luca Brasi, Clemenza, Tessio, and probably Sonny carrying out the muscle work. Now Rocco, Cicci, and Neri have assumed those roles. I’m sure it’s been brought up before but it’s interesting

Yes. One thing Coppola wanted to do (per his Notebook) was have Michael "emerge" as the don. You see little glimpses in various meetings, and it's finally full-blown when he visits Carlo.

I can't think of where I heard it, but I think Coppola talked about "succession" being a continuing theme of the first movie? It certainly is in the novel: very early, Vito thinks that Sonny wouldn't be a suitable successor as don. In the course of the war, the aging and mellowing of Clemenza and Tessio become a factor.

Couldn't have asked for a better musical score to accompany that scene.

On another level: Coppola blends violence into religious scenes in several key scenes in the Trilogy.