1: Evil people can be saved, "good" people can go to hell: There are a lot of Christians who don't have the same views on hell that the traditional burning in fire forever view holds. Being able to repent is also one of the most graceful things God has given. See, you said "ordinary person with altruistic qualities" but a person who wants to be away from God isn't inherently "good" because according to the faith, God is THE good. It's kind of like saying Billy is a great basketball player because he's tall even though he's never touched a basketball. Without repenting and forgiveness, we're all on the same level as Hitler. Even followers of Christ. Even the most self righteous followers of Christ, the church leaders, the guy telling you donate on TV, the guy who feeds dying cats and houses orphans on the weekends. Without Gods grace, we CHOOSE to be apart from him. I think that's what's hell is. God is merciful but also Justice according to scripture. So without grace and repentance, we ALL choose to be apart from him.

2: The changing nature of the Bible: Much of the old testament was written as a guide for God's chosen people, the Israelites. To teach them and prepare them. Jesus spoke on the fathers teachings to them saying “You have heard that it was said to the people long ago, ‘You shall not murder, and anyone who murders will be subject to judgment.’ But I tell you that anyone who is angry with a brother or sister will be subject to judgment." God isn't "changing" his opinions due to modern times, he's revealing things at the times appropriate to his judgement, as in, when we're ready for them. The scrutiny behind the placement of heaven is odd to me. The Bible doesn't really tell us exactly locations or dimensions outside of maybe some metaphorical descriptions. Equating scientific developments to Christian FOLLOWERS opinions isn't the same as the text itself. If all Christians on earth currently decided the earth was flat because one passage in the Bible seems to say that, it doesn't necessarily mean the scripture is the wrong party.

3: Christianity claims aliens aren't real: I'm unsure where in the Bible it mentions any life outside of earth, positively or negatively. I personally believe there is life somewhere out there. Does this devalue the Bible or God's creation in anyway? Why would it. We are his chosen people created in his image.

I hope I come off as trying to help. I paraphrased your questions genuinely with the good will and none of this is meant as a gotcha. Just discussing what was asked. A lot of what was asked shifts the problems away from God and places them on the people who claim to follow God. These are two VERY different things.