Abraham wasn't a gentile, he was the first hebrew. This means he has crossed over from death unto life through covenant. Why was Abraham picked?
Gen_26:5 Because that Abraham obeyed my voice, and kept my charge, my commandments, my statutes, and my laws.
and
Gen 18:19 “For I have known him, so that he commands his children and his household after him, to guard the way of יהוה, to do righteousness and right-ruling, so that יהוה brings to Aḇraham what He has spoken to him.”
As with so much of your theology, you have this exactly back to front.
God did not 'pick' Abraham because he obeyed God's voice etc.; he chose him in order that he should do so. Abraham was an idolater in an idolatrous family before God chose him Deuteronomy 26:5; Joshua 24:2-3). Like the rest of us, Abraham fell short in many different ways throughout his life, but God persevered with him because He loved him.
But you yourself don't do it, so how do you have the gall to tell us to do it? You do not obey the sacrificial laws which are just as much of your 'Torah' (Not the word used by the Lord Jesus, so you are altering His word) and for the rest you merely 'try' to obey them.. You 'bind heavy loads, hard to bear, and lay them on men's shoulders...' but you will not move them with one of your fingers (Matthew 23:4).The people group that the promises are directed at is indeed Israel (both physical and spiritual as you say). It has defined borders, a defined Elohim (king), and his defined laws, . This makes up the kingdom. All those wanting to be part of this kingdom have to come in and join this group, their king, and his laws.
You have not yet explained how your righteousness exceeds that of the scribes and Pharisees. Ezra was a 'skilled scribe in the law of Moses' (Ezra 7:6). Saul was a Pharisee, 'advanced in Judaism beyond many of my contemporaries in my own nation' (Galatians 1:14), and 'concerning the righteousness that is in the law [The word is nomos, the same word that you translated 'Torah' in Matt. 5:17-18], blameless' (Philippians 3:6).
Why do you think your righteousness exceeds that of scribes like Ezra, and Saul of Tarsus, because if it doesn't, you 'will by no means enter the kingdom of heaven' (Matthew 5:20)?