Why would you believe in a God whose morality isn't superior to yours? Conversely, if you care for those around you and you knew God's will was ultimately better for them, why would you not obey Him over your own judgements?
I'm not arguing that God's morality is somehow inferior to mine - I'm arguing that by trusting and obeying Him over my own moral judgement (I know murder is wrong, yet God tells me to kill someone), I am shifting responsibility for my own actions onto Him - Abraham's greatness is that he does not doubt the Lord. The ultimate accountability to God is inherently at odds with my responsibility for those around me.
"He that loveth father or mother more than me is not worthy of me: and he that loveth son or daughter more than me is not worthy of me." Would you look your son in the eye as you lower the knife?
> The ultimate accountability to God is inherently at odds with my responsibility for those around me.
If you believe that God is more loving than you are, it is not at odds at all. In fact, if you want what's best for those around you, you are responsible to obey the Lord first and foremost, as he loves those around you more than you do. He also loves you more than you love yourself.
If, however, you don't trust in God's love, then you're totally right. You'd be obeying someone who you're not sure has your neighbors' best interest at heart, and thus abdicating your duty of care.
God ultimately saved Isaac so I'm not sure why Abraham's sacrifice would be a counter-example to God's love here. We can talk about all the people who actually died, seemingly by God's orders, in the Old Testament, but we don't know what happened to these people ultimately, given redemption and salvation by Christ. Death itself being conquered and eternal happiness being granted makes death a poor example of injustice.
I do believe we are talking about slightly different things here - you put an emphasis on God's love and His care for the world, while I focus on the human (Abraham's, etc) need to renounce the world and (by extension) the ties and moral responsibilities that bind us to it, in order to fully embrace God. Regardless, I'd like to thank you for taking the time to chat - I've had fun trying to work through and structure my thoughts on the topic.