I dont think any of the live action parts are really needed, but their not unwelcome either. The ending is long, but good. The Duplo invasion could be enjoyable. If they tie in all of the other knock off legos too, it could be very interesting.
I'm conflicted as to if there should have been more overt advertising in the movie or not. I liked the way they told you part numbers and think I would have liked that more often, but very creative of them to find a way to label parts without making it sound like a commercial for legos.
Everything about the movie is awesome.