Scriptures do not speak. People read scriptures and interpret them as they read, and since people all interpret them differently that is why there are so many different interpretations. If everyone who read the scriptures interpreted them the same way, then everyone would agree and there would not be so many disagreements among Christians and so many denominations of Christianity.
Whenever people say that scriptures speak plainly of the truth of the matter what they are really saying is that they know what the scriptures mean and that implies that anyone who does not agree with their interpretation is wrong. The sad thing is that these people cannot even understand how arrogant that is.
Jesus never said He would return to Earth to establish a Kingdom; not even once in the entire NT did Jesus ever promise to return to Earth. Rather, Jesus said:
John 17:4 I have glorified thee on the earth: I have finished the work which thou gavest me to do.
John 17:11 And now I am no more in the world, but these are in the world, and I come to thee. Holy Father, keep through thine own name those whom thou hast given me, that they may be one, as we are.
Unlike many verses in the NT, these verses have only one plain meaning, a meaning millions of Christians choose to gloss over because they want Jesus to return, but wanting something does not make it come to pass.
He does tell us that He Himself will return. Many times, speaking of Himself as the Son of Man, he says (to paraphrase), “You will see the Son of Man seated at the right hand of power, coming in the clouds with angels.” In the book of Acts (1:11), after the Ascension, two men (really, they were angels) who were with the disciples speak of His Return,
“Men of Galilee, why do you stand looking into the sky? This Jesus, who has been taken up from you into heaven, will come in just the same way as you have watched Him go up into heaven.” (New American Standard Bible)
As far as Him establishing His Kingdom on the Earth, in the book of Revelation, we see Him building a new Jerusalem on the Earth and sitting on the throne of King David as the Messiah. I know of no Christian who disputes these things.