How might the reader's connection to the plot/characters change if the story were told through a different point of view or through the eyes of a...

This is an excellent question because it causes the reader to really think about the narrator of the book in relation to the other characters.  Let us look at the narrator first, and then figure out how the story might be different from other characters' perspectives.

The narrator, of course, is Misha.  He is very much an innocent orphan who is only called "Stopthief" until he is "born" when Uri gives him the name "Misha."  We then follow Misha through his adventures with Uri's group of boys, his new friendship with a Jewish girl (Janina), and their travels to the ghetto of Warsaw, Poland.  Misha survives the Holocaust and eventually has a (dysfunctional) family of his own.

If the story was told by Uri, it would be quite different.  Where Misha is innocent, Uri is wise.  Uri is wise enough to dodge the "Jackboots," to hide out in places like cellars and stables, and to know that above all else to avoid being labeled as a Jew.  If the story was told by this character, we would hear a lot more about the realities of life in the Warsaw, Poland in the late 1930s.

If the story was told by Janina, the focus would be on friendship and compassion.  Janina is most certainly Jewish and proud of her faith.  She is less innocent than Misha, but not by much. If the story was told by her, she would talk lots about her Jewish rituals and why they are important to her.  We would also learn a lot about her friendship with Misha from a girl's perspective.

If the story was told by Misha's granddaughter, Wendy, it would be a very different story indeed.  It would need, then, to be written as a frame story, with Misha's life being the meat of the story.  Wendy, like her grandfather, would probably focus a lot on identity and the fact that it was her grandfather that bestowed his upon her.  She would also talk about bestowing him his real family identity by calling him "Poppynoodle."

So, as you can see, depending on the character telling the story, the focus would shift greatly depending on whether it was Uri, Janina, Wendy (or even another minor character not spoken of here).