The following is from my own understanding and knowledge which could be faulty.
As I mentioned before, this was the test that the humans (and I suppose Jinns are also included here) accepted. God of course knew that some will follow Him and others will disobey Him, but (according to the Islamic doctrine) humans chose this test out of their own free will, they were not forced into it.
He does not "need" our worship, but He would be pleased if we succeed in our tests.
Everything we know about God, comes from the Qur'an and authentic Hadiths. They along with some other attributes of God do talk about the pleasure and displeasure of God. Therefore, these cannot be denied (although there are some groups of Muslims who try to give metaphorical meaning to clear statements from scripture about such attributes, but from what I know that is not the majority opinion).
Regarding whether such attributes can be related to any human like emotion, from what I understand, we just don't know. Like the eyes example I gave before, we just have not been given enough information to say much for certain.
All we can say with certainty is what Islam tells us, which is, that God is pleased by those who follow Him, and displeased by those who disobey Him; exactly what is the nature of that pleasure and displeasure or what accompanies them, if there is anything, is not certain (although "crying" is, I suppose, definitely something beneath God).
Regards,
