You say that the purpose of Revelation was to give comfort, I say it was a warning. Also contained in this message to the churches is a statement of Christ's deity. There are some that are ignorant and do not consider this important, but if they would take the time to study and understand it they would be able to identify many false teachings.
Warnings Of course I am sure that you will acknowledge the warnings of chapters 2-4.
Other warnings concerning time.Revelation 22:10
10. And he said to me, "Do not seal up the words of the prophecy of this book, for the time is near.
Revelation 22:12
12. "Behold, I am coming quickly, and My reward [is] with Me, to render to every man according to what he has done.
Revelation 22:20
20. He who testifies to these things says, "Yes, I am coming quickly." Amen. Come, Lord Jesus.
DeityRevelation 22:16
16. "I, Jesus, have sent My angel to testify to you these things for the churches. I am the root and the descendant of David, the bright morning star."
Revelation 1:8
8. "I am the Alpha and the Omega," says the Lord God, "who is and who was and who is to come, the Almighty."
To your question:
“Should these verses be read with an expectation of fulfillment to happen shortly, at hand, quickly or should we expect fulfillment thousands of years into the future?”
God's promises and warnings in Revelation were not just to the seven churches, they were to all mankind, listen to what Peter has to say.2 Peter 3:5-11
5. For this they willingly are ignorant of, that by the word of God the heavens were of old, and the earth standing out of the water and in the water:
6. Whereby the world that then was, being overflowed with water, perished:
7. But the heavens and the earth, which are now, by the same word are kept in store, reserved unto fire against the day of judgment and perdition of ungodly men.
8.
But, beloved, be not ignorant of this one thing, that one day is with the Lord as a thousand years, and a thousand years as one day.
9. The Lord is not slack concerning his promise, as some men count slackness; but is longsuffering to us-ward, not willing that any should perish, but that all should come to repentance.10.
But the day of the Lord will come as a thief in the night; in the which the heavens shall pass away with a great noise, and the elements shall melt with fervent heat, the earth also and the works that are therein shall be burned up.
11. Seeing then that all these things shall be dissolved, what manner of persons ought ye to be in all holy conversation and godliness,
A lot what is described in Revelation will occur after the rapture, after the church is been removed, and is not meant to comfort but to
warn those who are not right with God.
For instance:
Revelation 9:3-6
3. And there came out of the smoke locusts upon the earth: and unto them was given power, as the scorpions of the earth have power.
4. And it was commanded them that they should not hurt the grass of the earth, neither any green thing, neither any tree; but only those men which have not the seal of God in their foreheads.
5. And to them it was given that they should not kill them, but that they should be tormented five months: and their torment was as the torment of a scorpion, when he striketh a man.
6. And in those days shall men seek death, and shall not find it; and shall desire to die, and death shall flee from them.
It is impossible to study the Bible a verse at a time without considering the whole context.
So I say to you that the purpose of Revelation
was not to comfort the reader, even though I do agree that many of us do take comfort in understanding the future given to us by the Lord Jesus Christ through John.
Study Scripture not me.