1. God is perfect, but needs to be worshiped
A perfect being by definition needs nothing. The canned theological response would be that worship is for us, not God. But if God doesn't need to be worshiped, why would he create beings who need to worship him?2. God is omniscient (all-knowing), but has free will
A being that is all-knowing knows the past, present and future. He knows all decisions that have been and will ever be made, including his own. This implies that he lacks the ability to make a choice, because he already knows all his future actions. He can't just change course, because he would have to know that he will decide to change course!3. God loves everyone and desires everyone to be with him, but created people who he knew would go to Hell
God's omniscience carries with it another conundrum: he knows all people's actions as well. He knows all thoughts, beliefs, actions, and the processes by which people arrived at them. He would necessarily know that certain people will reject him and that others will commit great atrocities, and that these people will not only inflict great suffering on others (in the case of the latter) but spend eternity in Hell.
God's omniscience has another implication: that he created mankind knowing that they would rebel against him. And to think he acted surprised!
4. God created ineffective covenants to redeem mankind
If God is perfect, why couldn't he get the whole covenant thing right the first time? He created a covenant with Noah that failed. Another with Moses that was incomplete. A new one through himself (Christ) that is also incomplete. He won't fully complete things until his miraculous return, after a great battle between Heaven and Hell (I wonder how many Christians actually believe that). But if God is all-powerful, why couldn't he just make one fool-proof covenant? And why a great battle? Can't he just will it, and *poof*, the bad guys go away?5. Jesus sacrificed himself to God on our behalf, as a blood atonement for our sins
Except Jesus is God. God is sacrificing himself to himself to repay an arbitrary price (why do we need blood atonement, specifically?) for a curse he put on us after we rebelled against him, which being omniscient he knew we would do before he created us.
I figure that's a good start. I'm open to suggestions.