You've missed the Spirit of God if you think He isn't grieved when man turns against Him. These are just a few examples of God grieving for His children. The fact that unbelievers reject Christ does not mean He does not grieve them... It's because He loves them that He grieves them.
In Ezekiel, "getting no pleasure in death of the lost" implies it's more of a negative feeling than a positive one, yes? Perhaps He is grieved as any father would over a son who is lost?
In Genisis, I believe you missed the meaning of that passage entirely. God "regretted" making man why? Because of the wickedness of mankind at the time (minus Noah). Your interpretation is that God grieved over making man... Please reread:
Genesis 6:5-8
5 The Lord saw how great the wickedness of the human race had become on the earth, and that every inclination of the thoughts of the human heart was only evil all the time. 6 The Lord regretted that he had made human beings on the earth, and his heart was deeply troubled. 7 So the Lord said, “I will wipe from the face of the earth the human race I have created—and with them the animals, the birds and the creatures that move along the ground—for I regret that I have made them.” 8 But Noah found favor in the eyes of the Lord.
You seem to think grieving is somehow condoning what someone has done in their life. That is not definition of grieving. God loves us and it pains Him when we turn our back on him. Even though God was going to wipe the wicked people off the face of the earth, He doesn't take pleasure in doing this. It grieved Him. We must remember there are consequences for our actions (sins), and that just because God is orchestrating an event to wipe out mankind, it doesn't mean He doesn't grieve His lost children. "Love" and "grieving" go hand-in-hand as I'm sure you know this as you mentioned the other day you're a father. I hope you reconsider your interpretation.