If God wants people to follow Him, He will go to them in whatever way He decides to take be that through someone or acting on His own accord. But it is always God acting just as He did with Nathanael.
...who then taught people the Word. What's the problem? People are still involved in spreading the Word of God. God uses prophets and preachers to do this. So God chooses to save people through other people. We receive faith by hearing the Word being proclaimed. Naturally, the vast majority of people will hear this Word through the voice of another person.
If God wants people to follow Him, He will go to them in whatever way He decides to take be that through someone or acting on His own accord. But it is always God acting just as He did with Nathanael.
Of course, as I said, God works through other people, allowing them to participate in the salvation of others by spreading the Word.
If they are made in such a way that their free will chooses God, why doesn't God make everyone in that same way?
I would say that God predisposes people whom He wills to choose Him - and since He sees all time as one present NOW, He is aware of what will be necessary on our part to react to His promptings. Again, you keep forgeting about how God and time interact. God has access to the past, present and future simultaneously, not in a linear way like us. Thus, His interactions are done at the same "Now" that we make our decisions.
This contradicts what you just said about Jeremiah.
Jeremiah freely choose God and God provided the necessary graces that Jeremiah would indeed choose Him. Again, I can't explain how God predetermines our response coupled with His judgment of whom will be of the elect. Since this is a mystery, we cannot fully understand the interaction between God's predetermination or man's free will. When we come to a mystery, we accept both sides as truths without understanding the full explanations on their interaction. We DO know that this is not a contradiction. It is just not fully explainable, much like Christ's presence in the Eucharist, or the Divine Trinity.
God ordains our steps.
He does this simultaneously with seeing our response to His Will. That is the best way I can explain it. For if God "ordains" our steps in the way you seem to imply, we no longer have responsibility for our actions. Is this the message you get from Scriptures, that we are not responsible for our actions?
Regards