The highlight is the public reveal of Ace’s father. For many first-time viewers, the shock that Gol D. Roger is Ace's father recontextualizes the entire relationship between Luffy and Ace.
Seeing Garp sitting next to the execution platform, torn between his duty as a Marine and his love for his "grandson," adds a layer of "soap opera" drama that critics find highly effective. 📺 Recommended Reactions & Overviews One Piece (Dub) Episode 459
While some background animation can be static, the wide shots of the Marineford crescent bay effectively communicate the "Avengers-level" stakes of the conflict. Key Highlights The highlight is the public reveal of Ace’s father
I can help you keep track of the many characters involved or explain the specific powers of the Admirals if you're interested! One Piece (Dub) Episode 459