To your first question, let me make a short summary of my timeline.
I'll use fictitious calendar years, just to make the point
- 1,500 BC - Law is given to Israel
- 720 BC - ten northern Tribes carried away
- 600 BC - two southern Tribes carried away
- 530 BC - 2.5% of Judah and Benjamin return to rebuild Temple and later the City
- 4 BC Jesus is born
- 30 AD Jesus is murdered
- 70 AD Judah and Benjamin dispersed
- 70 AD - 2030 AD Israel chastised
- 2030 Israel, a new State, embrace the Beast and allow him into the Holy Place
- 2033 Second coming of the Lord, Armageddon, and Israel resurrected and gathered (Ezek.37)
- 2034 - 2130 Millennial Kingdom (Messianic Kingdom) ON EARTH
- 2131 -2140 Magog gathers an army and rebels, is defeated and God has White Throne Judgment
- 2141 - the "ages to come" on the New (Renewed - lit. Gk.) Earth
I say again,
the dates are fictitious. I make no claim to knowing any date after 70 AD.
To your second question I have the same problem as you. But I think the answer is in verse 5, in the word
"prevailed". "And one of the elders saith unto me, Weep not: behold, the Lion of the tribe of Judah, the Root of David, hath prevailed to open the book, and to loose the seven seals thereof." The words "hath prevailed" imply a dispute, or an argument in which one is victorious. It would seem, and I cannot prove this, that God set a standard for anyone to be worthy. A time passes in which heaven waits to see who will claim this worthiness. After a suitable wait, our Lord steps forth in His dual capacity as (i) King of Israel by Covenant between God and David, and (ii) firstborn of creation, making Him the Root of David. But we must then ask; Why these ranks and not one of the many other high ranks of our Lord Jesus?
I cannot answer. I can only surmise that the events that precipitate the Great Tribulation take place in Jerusalem - "the City of the Great King ... where Jesus was crucified". I say this because the following verse alludes to Him being the Lamb and being slain. It was Pontius Pilate, representative of Rome, who ordered a placard on the cross "King of the Jews". In 30 AD therefore, it was Jerusalem verses Rome. The Abomination of Desolation is again Rome verses Jerusalem. And again it is Caesar verses Jesus. Pilate, who should have represented Rome, agreed that Jesus was of David's House. But this time, Jesus comes, not as the suffering Son of Joseph, but the rampaging LION of Judah. It is from this Seat that Jesus will rule the world after His return (Zech.14:16).