What I always keep in mind is that The Bible was written by people. It may be "the word of God" but Moses, John, and a lot of other humans wrote it.
As such, Moses wrote a lot of things based on his chats with God on Mt. Sinai. At some point, it was time to write everything down, what it means to be a "good" person. The passages in Leviticus seem quite simplistic to me. The purpose of sex is to reproduce; homosex doesn't not result in reproduction, therefore it is using one of God's gifts improperly, therefore homosex is "bad". What that attitude completely ignores is that God wants us to enjoy sex. Why would he give us such a gift and not expect us to enjoy it? Sex is not solely for the purpose of reproduction, but for expressing love and affection.
In other words, Moses meant well, but unless God specifically told him during one of their chats that homosex is a sin, then it was Moses who wrote it, not God.
Similar thing with the New Testament. John was a great guy, one of the best, and knew Christ's mind about as well as any man could, but he was still just a man. John wrote a lot of things in his letters about what is right and what is wrong and what people should do and what people shouldn't do. But what I notice is that the gospels record many of Christ's sermons and teaching, and none of them record Christ ever speaking against homosex. Only John's writings.
In other words, John meant well, but unless Jesus specifically told him during one of their chats that homosex is a sin, then it was John who said it, not Jesus.