If Jesus came only to save you from sin, you have the right idea — but not the whole idea. Romans 5:17 says those who receive the abundance of grace will reign in life through Jesus Christ. Not someday in heaven. Now. In this life, in this body, in the circumstances you are actually in. He didn't just come to rescue you. He came to put you in a position of dominance over the things that were trying to subject you.
Adam started sinless. Jesus was born sinless. And when you were born again, you were placed before God in the exact same condition — pure, holy, a new creation. The problem is not what God has done in you. The problem is that your mind has not caught up to it. You keep reaching back to the old things as though they still define you. But 2 Corinthians 5:17 says old things have passed away. Not fading. Passed. The ceiling you are bumping is not God's ceiling for you — it is the ceiling of your own unrenewed thinking.
The abundance of grace is not something you are waiting to receive. It was given the moment you were born again. You already have it. The Spirit of God that raised Christ from the dead lives inside you. That same Spirit brings conviction when you are going the wrong way and gives you the ability to say yes to God and no to the flesh. What you do with it is now on you. The grace is not missing. Stop overriding the Spirit and start yielding to what God has already placed inside you.