"Why do it again if you can’t do it better?"

That's the question that Joss Whedon is asking himself about 2015's Marvel epic "The Avengers: Age of Ultron."

Although he was mostly happy with the end result of 2012's "The Avengers," the writer-director told EW that he's hoping to deliver an even better thrillride with "Ultron."

"There was haphazardness in the way it comes together—not just the people, but the scenes," he says about the first film. "I don’t think you’d look at it and go, ‘This is a model of perfect structure.’ You’d go, ‘This is working.’ I like it. I’m proud of it and I like its imperfections. The thing I cared most about -- making a summer movie like the ones from my childhood -- is the thing that I pulled off.”

For the sequel, Whedon says "I want to be clearer about how I engage the audience, and where I take them. I want more control visually, more time to prep it. Not that I didn’t dictate every shot [in 'The Avengers'] -- I did. But there’s only so much you can do when you’re making a summer film when the ball is already rolling as fast as it was when I got in. Why do it again if you can’t do it better?”

"Ultron" will cap Phase 2 of Marvel's Cinematic Universe and will reunite stars Robert Downey Jr. Chris Hemsworth, Chris Evans, Scarlett Johansson, Samuel L. Jackson, Jeremy Renner and Mark Ruffalo. James Spader has signed on to play Ultron, while Elizabeth Olsen is reportedly in talks to play the Scarlet Witch. 

After the sequel wraps, Whedon also hopes to take on a bigger role on the TV spin-off, "Agents of S.H.I.E.L.D.," if it's still around in 2015. The move would mean putting another dream project (a new take on Shakespeare's "Hamlet" on the back burner. 

"If everything works out according to plan, 'S.H.I.E.L.D.' will be on when the movie is over and then I’ll already be too busy [for 'Hamlet']."

"The Avengers: Age of Ultron" will be released May 1, 2015.