Perhaps the best way to describe the structure of the two games in order to set proper expectations would be this: (This is not a spoiler, just some slightly expanded insight on the story structure)
I read that Shu Takumi once said in an interview that his original vision for the first Ace Attorney game would be that the events of 1-2 would be the final case in the game and that there'd be other cases between 1-1 and 1-2. He was told he couldn't do this though because it would be too slow of a start.
Great Ace Attorney 1 is what happens when he gets his way.