I think this movie is more of an ode to Kubrick by Speilberg in many ways, but on the other hand, the developments by Kubrick for making this movie feel like Kubrick wanted to make a movie closer to the heart Speilberg had in his movies. It wouldn't be for the first time he did this though, because I am pretty sure The Shining was influenced by Jaws and how Speilberg approached the story. He had other stories to it than just the shark one, but it was a movie completely within its genre that did nothing to bring up drama over the terror of the shark. The ending was the shark being killed and thats it. Kubrick's The Shining very much based itself off that in showing the action scenes in a similiar way and building up of the suspence. Yes, it was Speilberg doing a Hitchcock movie in many ways but there were more elements like a story between people instead of just the suspence that prolly proved more influential. And in all the interviews of Kubrick, I've never once heard him even mention Hitchcock but I could have missed it. I think Kubrick had an admiration for Speilberg, in that at his best, he could mix the fantasy of Movieland with a very personal story and show emotions a lot of other directors would feel too good to show. In preparation for A.I., Kubrick talked highly of how much he admired E.T. and wanted something of the similiar feeling to his story of Pinnochio retold. I think Kubrick honestly wanted to show that, but would have failed and in return, what he would have created would have been much more cold and distant and then interpretated by many as being for a purpose. But I think he really wanted to make his own E.T.
Then there is the relationship of Speilberg wanting to be more like Kubrick and how he did marry themes of himself and Kubrick within the story. I don't think the story ever was really finished and if Kubrick did have a chance to make it, prolly wouldn't have finished it for another ten years minumum. Kubrick always went into films not really with set goals of what exactly to film in such and such time frame, but always trying to discover something through the process of shooting and editing. Also, A.I went through many many different stages and ideas and Kubrick went down the line of science fiction writers he was writing with. I think the end result shows his indecision by having an ending that seemed very similiar to 2001: A Space Odyssey, and showing a city that was reminiscient of A Clockwork Orange in feeling and style. I think Kubrick would have changed these details for the most part while keeping a movie that did focus on the Pinnochio aspect for the most part. In the end, I think the movie basically was Speilberg doing a movie that was very much of an ode to Kubrick without fully evolving into its own identity.
the questions I am confident to answer because to have not seen movie in a while,
3.) He did model it after his dead son, but he is a businessman too who realized he had made something very valuable too. In honoring his dead son, maybe his likeness being the official image to how far machines have come was important to him. If he kept his dead son in a very respected way that was to keep it private and to himself, maybe he wouldn't have created a machine like him. But I think the main aspect of that detail is to show David coming to the realization that he is no longer unique and a machine that can be mass produced.
4.) The aliens at the end very much go towards Kubrick's own beliefs to how aliens are. In many interviews during 2001, Kubrick always attested to the belief that if there were aliens evolved enough to build spaceships to travel so far in the galaxy and such that it would be safe to assume that their brain development would be that high too and they would be very peaceful and understanding instead of being all kill kill like popular culture has said.