Does God ever choose a common man, of common desires of frustration and mockery to prepare His people?

Yes.

1 Cor 1:26-29

For you see your calling, brethren, that not many wise according to the flesh, not many mighty, not many noble, are called.

But God has chosen the foolish things of the world to put to shame the wise, and God has chosen the weak things of the world to put to shame the things which are mighty; and the base things of the world and the things which are despised God has chosen, and the things which are not, to bring to nothing the things that are, that no flesh should glory in His presence.

Almost all of the people who God used in the Bible were ordinary, no name people. All the apostles were fishermen, and Peter was always putting his foot in his mouth and even denied Jesus 3 times. Think about Moses, Job, Jeremiah, Jonah, David, Noah, Paul, Ester, Naomi, Ruth, John the Baptist. No one was known at all outside of what they wrote in the scriptures. You and I can be used as well today to prepare people for His coming. God uses people and all people start out as sinners and common and frustrated and at times mockers. He doesn't use perfect people because there aren't any. All we need is a willing heart and He will do the rest.

There has been a pattern of the weak ones as to the world being chosen as His prophets. Moses for instance was not a very eloquent speaker. He was terrible.

John the Baptist.Paul

All of the prophets were mocked, ridiculed and frustrated.

Moses was born a poor Jew and had a problem with his speach.