Why doesn't God just destroy us all? Genesis 4-7

Why doesn't God just destroy us all?  In Noah's day it is said in Genesis 6 that God saw the evilness on the earth and was "sorry" He never made man. So, why not just destroy them and start over?   God put together a plan for Noah to build an ark and bring the animals two-by-two into the ark to save them.  Why not just destroy them and start all over again?  It is not like God can't create.    Why save Noah? Today the world must be, at least, as corrupt as in Noah's day.  Why not destroy it all and start afresh?   One verse answers all these questions as to why God designed the ark and rescued Noah and his family:

Genesis 6:8

But Noah found favor in the eyes of the Lord.

Noah found "favor."  The word is actually the Hebrew word for "grace."   Noah found grace in the eyes of The Lord.   The reason God didn't just destroy the entire earth and start over was to show the marvelous depths of His loving grace.   The reason God doesn't destroy our world today is the marvelous grace He is wishing to bestow on us.   He sent His son (a type of ark) to rescue us from the impending doom of this earth.  All who "enter" Jesus will partake of God's grace.   Just as the animals and Noah and his family "entered" the ark, so too, we, "come into" Christ to receive grace from the fiery doom set to destroy this earth .... this time for good.   God is going to "just destroy it all" but not until He offers grace to mankind.   God didn't destroy the entire earth in Noah's day because Noah found God's grace.  God is a gracious God no matter how evil we as men can be.   Why doesn't God just destroy us all?  Because He is a gracious God.