I want to see a Blu-Ray 'super-cut' of the two films.
Use the narrative device/structure of the first film(Dilios narrating before the battle of Plataea) and simply cut in all of the events and sequences of Rise of an Empire where they occur chronologically.
Drop the Gorgo narrating device from the first film, and bring in David Wenham to do additional narration voice-work to 'bridge' the two narratives. So that the entire thing is Dilios telling the story.
I'd also consider dropping the entire Gorgo sub-plot from the first film. None of her early scenes...but everything once the 300 leave Sparta is a little unnecessary, her dealing with Theron, speaking in front of the council and revealing Theron to be a traitor.
In the scheme of a 3.5 hour mega-movie, that sub-plot would have decreased purpose.
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