This is actually my first attempt at quoting. Let's see if it works.
The "official" response is that we were created perfect, but Adam & Eve screwed it up, so we are ALL screwed. God, however, threw us a life-line. All you have to do to escape is turn from sin and follow Jesus. God's rules, so he can define sin how he wants. Should being gay be a sin? I would tend to exclude that from the list, but it is not my choice.
Regarding the apple story: putting the apple in the garden when he KNEW they would eat it was supremely assholish. Yeah, he told them not to eat it. Yeah, they did anyway. BUT WHY PUT IT THERE IN THE FIRST PLACE? Oh, they had to have a choice. Well, why? If you're designing a UI, you don't have a big button on the screen saying, "DON'T CLICK ME, BUT, IF YOU DO, MAYBE SOMETHING GOOD WILL HAPPEN!" and then have that button format the hard drive. As a general rule when creating devices or environments people interact with, you try to make it hard or preferably impossible for them to screw things up for themselves, not easy. If you're nice, you try NOT to give them choices they don't need and which can only serve to hurt them. He gave them a choice when he knew they'd make the wrong one. That's worse than stupid: it's mean. It's psychological torture. It's like:
"Yah, things could have been great for you guys but you FLUNKED. HA HA ha. Ha ha. Ha."
As to heaven vs. hell, let's look at things differently. If you do assume heaven and hell exist, then who gets to go where? Would you like to think that Hitler is in hell? How about Stallin? Putin? The guy who cut you off in traffic last week? The guy who sold you the broken used hard drive off of CraigsList and told you it was in great shape? Simply stated, if you just judge people on good/evil, where should the dividing line be? What about the person who is just below this imaginary line? How should they feel? To a perfect being, the ONLY line that makes sense is perfection. Nobody lives up to that, so God had to invent an escape plan.
Personally, I don't think anyone "deserves" to suffer. An eye for an eye just isn't how I think about things like that. It's like, a dog bites someone, so you torture the dog. Why do that? It's a dog. Kill it if you need to; don't make it suffer.
Most of the time, at least in my opinion, people who do assholish things don't really know they're being assholes. They had bad parents who taught them a screwed-up morality system. Or, they fail at logic. Or, they're too self-centered. Or, they fall into blame-the-victim fallacies because of who knows why. But, they're not really evil. They're just wrong. If you can get to them -- really get them to listen to you -- maybe you can make them right. Maybe not. But either way, there's no excuse for being cruel.
Sadists are the people I have the most problem with. People who intentionally cause other people pain just for the sake of doing that -- I mean, I can't empathize with them. At all. They're more alien to me than, well, dogs. Even dogs can show kindness, to their owners and to other dogs. People who can't, well, they're freaks of nature, and they're scary, and they're tragic, and my understanding is they often can't be helped. I look at them as deformed to the point that they can scarcely be called human. And that's sad.
But I don't want to torture them. Lock them up if you have to (assuming they committed a crime). But why would you want to hurt them? What would that accomplish except satisfying your own vindiction? And vindictiveness if a character flaw.
If I were hurt -- badly -- by a sadist, maybe I would like to see them suffer. But that's because I'm not perfect; I am sometimes vindictive. However, it would take a lot -- a lot a lot a lot a lot -- to make me want to torture them for all eternity. If I got to where I would want to cause that much pain, well, the sadist won, in a way, because I'd have become a sadist, too.
God -- if you're Christian -- has people tortured for all eternity, as a matter of course. He does this to a substantial portion of humanity. He supposedly outsources the job to one of his former lieutenants with whom he had a falling out, okay, so what? We're his CHILDREN, RIGHT?! If the God you're talking about is real, and he's sending people to Hell, the world is as dark as dark can be, because we're the playthings of a sadistic monster.
Regarding Jesus: afaik there's little to no evidence he lived outside of the Bible, which I don't take to be a reliable source. I have no idea if there was a man named Jesus Christ, and the question doesn't really interest me. I've actually looked at the specific book you pointed out, and I found it unpersuasive. You have to be careful reading that book: a lot of the stuff he says is just plain factually wrong.
Regarding the environment of Jesus: assuming he was really a person, he was born into a time when Judaea had a lot of revolutionary theocratic political movements going on, many if not most of which involved leaders claiming to be the Messiah. There were a lot of claims that miracles were being performed, too. In my view, Jesus is just the one who caught on. This actually, in my view, makes is more likely than not he /WAS/ a person despite the lack of evidence of his life outside the Bible. But, like I said, I really have no idea.
I wish I could bring up the specific Messiah claimants that I used to know about as examples of "Jesus alternatives", but it's been so long since I've debated this that I've forgotten their names, and Wikipedia was surprisingly unhelpful.