At any rate, ethical monotheism is certainly a belief of the Torah and in particular the doctrine that God is simple- not a composite. This incidentally is accepted by Christians also and is called "divine simplicity." However the Rambam has a few doctrines which are not from the Torah, nor from the Talmud. He expands the prohibition of idolatry to include the idea that God can be enclosed in body. This is certainly against the Talmud which has God clothing himself in a body to give a haircut to Sancheriv. It is also not the basic idea of idolatry of the Torah itself.
Also, in the Torah God does change his mind. According to the Rambam basing himself on Aristotle God can't change his mind. This simply is against the Torah. Point blank.
Another example is Job. The Talmud and the Rambam because of theological reasons can't accept basic premises of the Book of Job. The reason is that the book of Job goes against the book of Deuteronomy. But in the book of Job, the narrator makes it absolutely clear in the beginning that Job was innocent, and he was not being punished for any sin at all. This is an absolutely clear part of the narrative because without this the entire narrative falls apart. And in the end God says that Job was right and his friends theology was wrong. [This is also against Jewish tradition. His friends were saying the regular Jewish approach.]
Final note: Any system of human interaction, if brought to its extreme, will result in evil. finding bad things in the Talmud or Rambam does nothing to disprove the basic system.you can do the same thing with democracy. The problem with outreach in general is that it is based on the jelly bean argument. If you have only two jelly beans in a jar and you take out the red ones you are-left with the other one. An example of this type of argument is: since all gentiles are evil so the Torah is automatically right.