Yes, that’s a good idea, it’s a start. You’re among the first in this thread to present any solid ideas for a sequel, and I’m not going to be ‘Johnny Coldwater’ on the few contributions. Besides, we already had a thread about whether there should or shouldn’t be a sequel…
Yeah, I see them too as more like children. Although they have some adult traits: Wall-E and Eve both work for a living, they aren’t exactly in Conservation Camp.
They could, as you say, build a new child-like robot, perhaps to perform some essential task they don’t have time for, or the humans need and can’t find on the Axiom. Or perhaps they could adopt a malfunctioning misfit robot, one we haven’t seen yet. The Axiom is full of them. Also, there must be all sorts of broken down robots still around on earth that are salvageable. Wall-E will somehow have to find a new pet, the roach is in Wall•E1, but a new pet is in order. Kids have pets.
Ryan’s idea about another Wall-E is good too. Would it be possible to show another cuber with a decidedly different personality? How about a prequel showing the development of personality in Wall-E? Some of you might think that is boring, but nearly a third of Spiderman, Iron Man, and Batman Begins used this device. These were very big movies with a very big soul.
Another idea is what I said above: future toys. We see things like the singing fish in Wall-E’s truck, but how about toys of the future? They are sure to be little robots already (not just the quickly boring one-task toys we have today), and will capture our affections. Folks, someone is going to make a movie with these ideas. It might as well be Pixar.