Questions I have

My questions are as follows: 1: Why aren't Mormons considered Christians by a lot or most of the other Christian religions? I mean, if there could be no more revelation after the book of Revelation, then the whole Bible's false. That passage was saying that anyone who adds or takes away from that book will be destroyed or something, right? Well the Book of revelation was written before any of the other Bible books. So logically, the Bible is false if that is what that statement means. 2: If all the revelations and visions ceased after the apostles, then god is not the same always and he must be a changable god, right? I mean, if God spoke to us in the Bible, why would he not speak to us today? If he just all of the sudden stopped, then that means he is not always the same, right? Also if the apostles were killed in such brutal matter, and there were no more visions and revelations after them, that would mean there had to have been an apostasy, right? And it is because of the unbelief of the people and their wickedness that stopped all of this and miricles. That is what the Book of Mormon says and it makes sense because God would have to have taken his church and priesthood away from the earth and it's people. So 3: Why do Christians not bekeve in this. If you are open mided and look into it a little bit, you'll find all of the Mormon Doctrines of Kingdoms of Glory, Baptism for the dead, preexistence, ect in the Bible. Also there was no authority or prayer at Nicea. It is a historical fact that you have records of the deaths of the apostles and this would mean the Mormons are Christians, if not the only true church.