The Bible says there is just "one hope" for Christians (Ephesians 4:4).
Revelation says God will come down and bring Heaven down to Earth. (Revelation 21:2-3)
The Old Testament focuses more on the hope of the earth being a paradise and the New Testament focuses more on going to Heaven.
But as we can see Revelation and Ephesians, there is only "one hope," and we will get to experience both the paradise earth and heaven.
I see no reason in the Bible why we would need to take the number 144,000 literally in Revelation, where almost all the other numbers mentioned are symbolic.