Romans 1:1-4 Jesus the Descendant of David

Short one today, I did some looking into How Jesus is descendant from David, since Joseph was not his physical father.

1 Paul, a servant of Christ Jesus, called to be an apostle and set apart for the gospel of God— ² the gospel he promised beforehandthrough his prophets in the Holy Scriptures ³ regarding his Son, who as to his earthly life^[a] was a descendant of David, ⁴ and who through the Spirit of holiness was appointed the Son of God in power^[b] by his resurrection from the dead: Jesus Christ our Lord.

Theres heaps in here, but I just wanted to focus on Jesus' Genealogies. 
So in Matthew 1, we have the Genealogy os Jesus from the line of Joseph. After some research, I think Matthew did this because he was writing to the Jews, and they would only accept the Messiah from a male descendant of David. Joseph was legally Jesus' father, and so Jesus was Legally a descendant of Joseph. 
In Luke 3, we see a different Genealogy -  coming from David's son Nathan, and it could be argued that This is Mary's Genealogy. Verse 23 of Luke 3 says

Now Jesus himself was about thirty years old when he began his ministry. He was the son, so it was thought, of Joseph, the son of Heli...

Apparently in the original text, it says Joseph of Heli, not 'son' of Heli. It could be argued that a better translation could be 'son-in-law' or Heli. I'm not sure how feasible the explanation is, but it fits well. 

This also seems to fit with Jeconiah who is in the matthew 1 account, and in Jeremiah 22:24-30 is cursed along with his descendants. In comparison we have Zerubbabel in the Luke Genealogy, who was promised in Haggai 2:20-23 that the messiah would come through him. If he is in Mary's line, then God is keeping this promise directly. If Jeconiah is in Joseph's line, then God is also keeping his promise of the curse on his descendants, as the messiah is not Joseph's physical son Only by law.

Interested to hear your thoughts/ideas/opinions on this!