It's going to be somewhat difficult for me to answer all of your questions without basically creating a Bible lesson for a couple of the topics you have mentioned. I will try to keep things brief in respect to you and everyone who reads this thread. I'm not a fan of wordy posts that contain very little Scripture.
Now when I as an atheïst look at the old testament I see nothing but hatred versus various kinds of people including non-believers and women. Furthermore God kills thousands of people. How can this be the loving God that Jesus spoke of: anyone ever thought that for eternal punishment in hell the crime should be infinitely evil, and therefore cannot be done by men? Therefore any God who punishes with eternity cannot be good, so even if you claim that God had good reasons for these actions the mere existence of Hell would make him evil.
Number one, you're running on the assumption that what has been translated as forever (or eternal) punishment. You absolutely must go back to the Greek, in the case of the NT, to understand this. The reference is often to a plume of smoke rising on forever. I'm sure we can both agree from what little we know of the universe, we know it's vast. Where am I going with this? The plume of smoke example is a Hebraism. The punishment will not be eternal; you won't be tortured in a hell akin to a medieval dungeon. Revelation 21:8But the fearful, and unbelieving, and the abominable, and murderers, and whoremongers, and sorcerers, and idolaters, and all liars, shall have their part in the lake which burneth with fire and brimstone: which is the second death. Being cast into the lake of fire only happens once. Once you've been cast in, it's over and your name is blotted out and for all intents and purposes you exist no more. Getting back to the OT, it has just as much love as the NT. I'm reminded of Hosea 6:6... For I desired mercy, and not sacrifice; and the knowledge of God more than burnt offerings. That's love. Love takes many forms and sometimes it's a corrective measure. Think of the wayward son who spirals out of control into drugs and worse. That's God's relation to us. His people have gone whoring after false religions, affairs of the world that involve lust, greed, and the like, and have forsaken Him. How much is a father bothered when he has lost one son? Try multiplying that billions of times. The reason God is letting this plan flow goes back to the First Earth Age - and we have a study on this - when the rebellion in heaven occured. This rebellion broke the peace of the world that was. The people that rebelled did so because it desired stife and most importantly power. You can read about the condemnation of Satan in Ezekiel 28. This rebellion was built on hate. As far as I am concerned, God is giving us all every chance in the world to repent in such a simple way. Those who end up in the pit end up there solely because of their own lifestyle and choices. These people have the chance to accept the father - for God desires that all souls come to him - but if they do not then obviously they'll only perpetuate the hate. II Peter 3:9The Lord is not slack concerning his promise, as some men count slackness; but is longsuffering to us-ward, not willing that any should perish, but that all should come to repentance. When you mess with his people - through murder, rape, and the like - it will come back to haunt you and this is the message of the OT. When Cain killed Able, he was banished and cursed. When Amalek practiced ancient methods of what we today call terrorism, he was wiped off the face of the Earth. When Caananites and other relations of the Israelite attacked, they were taken care of. That's a father protecting his sons and daughters.
Now the second one: Darwin. See what I mean? Believers deny loads of evidence just to prove that the bible is correct, or in other words the old testament is correct, as far as I know the new testament does not contain scientific conflicts with reality.
The OT does not conflict. This Earth is billions of years old (again read the study I listed above). Job 41 describes a dinosaur. We have bones, carbon dating, and other evidences staring us in the face which does not conflict with the Bible. The problem is, people listen to churches deny the obvious in this arena and other even more important ones. We've forgotten, as humankind, how to read the Bible. The Hebrew tounges and Greek tounge is so much more complex than our language. Our words don't have the connotations that the Hebraic word might carry. The translators have done a good job; save some of the modern rubbish that "condenses" things. Enough survives in 99% of the translations to get to know the father; there are two levels though (Scripturally speaking): the milk and then the meat. Paul speaks in both cases: I Corinthians 3:2I have fed you with milk, and not with meat: for hitherto ye were not able to bear it, neither yet now are ye able. Hebrews 5:12For when for the time ye ought to be teachers, ye have need that one teach you again which be the first principles of the oracles of God; and are become such as have need of milk, and not of strong meat. Curiously enough, even then people failed to teach the true meaning.
Third problem: the old testament is not really Christian, Christian is the teachting of Christ, old testament is Jewish, however nearly everyone was Jewish when Jesus lived, therefore the church tried to unify the two religions, or perhaps it were the followers of Jesus in order to prevent proscecution.
Jesus quoted from the OT numerous times right down to some of his final words. Paul continually quotes things and Jesus expands upon the OT laws. Things like "Thou shalt not kill" make a whole lot of sense, and those came right out of the OT.