MiddlePath-
Your questions are excellent. Not that I have complete clarity in these issues, and no matter what, I think for any human being these concepts will always be seen through an ???????? ????? ?????, but there are some notes.
First, I think you would benefit greatly from reading Rambam. ???? ?????, his introduction to Avos, is a great place to start, and there is an English version available as well. Also, in his ????? ??????? in ??? the Rambam explains at length how we are supposed to understand reward and punishment etc. Then there is also the Moreh of course, and I could give you some ???? ?????? if you are interested.
Second, regarding your comment about morality: While it is true that there can be an unbeliever who lives a moral life by our definition, his morality is relative. That is not to say he won’t live and die by his morals. It is simply to say that those morals are subject to time and place, and every society in history has had different things they believed were right and wrong. Also, without being grounded in a belief that “God said so,” a thinking person’s mind can lead him anywhere. Nietzsche believed that there should be a master class that should be allowed to do whatever they see fit and only the rest of the world should have rules, and they should be slaves to the master class. I don’t know what he would have said about the Holocaust but you can certainly see how according to his line of thinking you might end up with people saying that there was nothing “immoral” about it. For any moral to be real, it needs to be grounded, and the only thing that can truly ground a moral is simply that “God said so.”