Jesus is God. Are you saying Jesus/God changed his mind about what is/isn't moral? Passover would seem perfectly moral to imperfect, iron age men who also thought it ok to kill their children to appease their gods. If we know that is wrong today, it would be literally impossible for God to not know something immoral now wasn't immoral then. He's God. He could have just "moved" them as he pleased or done any number of completely moral things to accomplish the same goal. Or he could have known, as an all-knowing being would, that his people were going to be enslaved and stopped it before it happened.
Many religions have evolved as religious behavior become untenable by MAN'S standards.
The Old Testament really seems to upset you. You should approach a Jewish neighbor or Jewish co-worker to complain about the Old Testament, since Hebrews are the ones who wrote it.
For the most part, I think you should either read the Talmud or consult with Jewish scholars about the interpretations of Exodus.
What I am saying is that, from the Abrahamic religious perspective, our human understanding of God changes through ongoing revelation. God did not write a single word in the bible. God did not even hand the bible to anyone from on high.
The bible is a series of books, letters, poems, revelations that humans wrote, and out of all the religious literature ever written out there, humans decided which would be canonical and which ones wouldn't.
So that means our understanding of God strictly comes from humans, and that understanding has constantly evolved through ongoing revelation, from the Torah, to the Na'vim of the prophets, to the NT gospels, to the writings of the Church fathers, to modern ecumenical councils and papal bulls.