I agree that believing involves man's will, but that will must first be freed and enlightened by God in order to respond rightly
And I've said that too. Grace must enable a man by suppressing the sin nature in the flesh so a man can respond as he desires not as th sin nature forces him to.
For example, the Lord opened Lydia's heart so she would pay attention to Paul's words (Acts 16:14)
Yes but God draws on what is already in the heart in order to open it. It is not a blank slate (at least not at the point Lydia was). This is why the scripture says God draws us to Christ. We are not soda cans where one pop of the lid and all the content is there.
My difference here is simply that man's fallen nature leaves him unable to see or seek God until he is enlightened.
I know. That is why God always initiates with grace and truth.
I see what you mean about man being created to respond, and I agree that blindness is the issue caused by sin (2 Corinthians 4:4). But the King James Bible never describes God as suppressing the flesh. Instead, it presents His work as enlightening and opening the heart and understanding.
If a man is bound to the sin nature and that nature is anti-God? How can he respond of his own free will? The will is bound and has to be unbound from what is binding it. Why do you think the Calvinists/Reformed hold to regeneration prior to belief? They see that as the "unbinding" instead of the salvation it is. God is light and presents us with grace and truth that is how He enlightens and opens our hearts. We are not some mindless automaton. God designed us with response ability so we can take responsibility for our thoughts, words and deeds.
Faith can certainly strengthen and deepen through obedience and experience, but it does not originate from human effort and later become divine.
I know faith doesn't originate with human effort that is why I said the power to create faith is in the word. My believing will get me no-where unless God acts. Thankfully for us God keeps His word, always. Of course, if what you believe is not the truth? You can kiss faith goodbye.
You can only ever have as much faith as you have truth.