Jeremiah 33 - confusing prophesies

As I read Jeremiah 33, he is speaking of God's faithfulness despite his people's great sin.  The first part of the chapter describes the great slaughter that will come at the hands of the Chaldeans.  But the whole tenor of the chapter is about God's restoration.  God will restore them as they were before.  Yet nothing really is said about their repentance.  Perhaps their condition is so weak, so dire, as to not even require repentance.  They have been brought to their knees.  But God promises, God vows to restore them.
Then the chapter takes a tangent.  In verse 33:15 Jeremiah speaks of the "righteous branch of David".  That can only refer to Jesus.  We see that now.  But Jesus has not really come yet to execute justice and righteousness in the earth.  Or has he?  Can we say that in his condemnation and death he judged us?  Is that what God is saying here?
Then is verse 33:17 he assets David shall never lack a man to sit on the throne of Israel.  Yet the kingdom did cease.  How can this be? Jeremiah adds, "There shall always be a Levitical priest to offer burnt offerings, to prepare sacrifices."  (That doesn't seem so important to us, but it did to them.)  Yet temple worship did cease.  How do we understand this claim?
From verses 19 to 26 the wording seems dense, hard to understand.  I do not clearly understand it.  Could that be intentional?
John Fieldsend picks up on 24.  "Have you not observed what this people have spoken, saying, the two families which the Lord has chosen, He has rejected them?"  What two families?
Fieldsend thinks this could refer to the two covenants that theologians has argued about since the church began:  Did God's covenant to the Jews fall away?  Did the church replace Israel as God's chosen people?  Fieldsend calls this thinking "triumphalism".  Or are there now two paths to God, one through Christ and one through the torah (old covenant)?
This discussion has been going on since the church began  Paul speaks to it at great length in Romans, especially chapters 9 - 11.
Perhaps Jeremiah's prophesy here presages all this.  Jeremiah is speaking to what happens when God's covenant is broken.  Christians see the Jews rejection of Jesus as a break of the covenant.  This is important to us  who break the covenant regularly.  Jeremiah concludes in 26, "I will restore their fortunes, I will have mercy on them."