I don't conflate the identity of the human and demonic characters. Are you familiar with the concept of "the divine council" in scripture? Back in the days of Peleg, God divided up the nations according to the number of the angels of God. In opposition to those righteous angels assigned to each of the nations, the "Prince of this world" had his own devils working against them - ultimately to no avail. One example on display in the scripture is the angelic "Prince of Persia" who resisted Daniel's angelic messenger and delayed his coming to Daniel until Michael the "chief prince" came to his aid. Behind the ancient kingdoms of the world, that hierarchy of righteous angels who were individually assigned to the nations of the world was one of the means God used to bring about His plans for those nations.
We have another example in Ezekiel 28:8-10, where the death of the human "Prince of Tyre" was predicted. This description was followed in Ezekiel 28:18-19 by an account of the eventual death of the "anointed cherub", who was also called the "Prince of Tyre", working behind the scenes of that ancient city.
It is the same with Satan working behind the scenes using the means of the human agent Herod to try to disrupt God's plans for bringing Christ the incarnate Redeemer into the world. To no avail, of course. This same evil intention shared between the human and Satanic / demonic agents to destroy Christ does not make Herod and Satan one and the same character, even though they had the same evil purpose.
No, the prophets did NOT "conflate imminent events with distant ones". In Ezekiel 12:21-28, God plainly stated that an "at hand" prophecy would NOT be prolonged into "times that are far off". God said that an "at hand" prophecy would not only be spoken, but it would be fulfilled in the days of the ones who were originally given that prophecy. You can't simply brush off God's own stated definitions of what He meant by an "at hand" prophecy. It is Preterists who correctly acknowledge the terms of imminence where they are given.
I have not dismissed the world empires being represented as Beasts. Daniel specifies the Chaldean, Medo-Persian, and Greek kingdoms as being the first of his 4 Beast kingdoms. Daniel's final 4th Beast was said to be unlike the other 3 Beast kingdoms. That is because it would be a conglomerate blend of the power behind all those former kingdoms subsumed into the final Roman phase of the Sea Beast, as presented to us again in Revelation 13:1-2. The seven kings of the Scarlet Beast of Revelation 17 were a subset of the Scarlet Beast. They were not 7 kingdoms themselves. That would be to add to the angel's interpretation of this.
As for the Land Beast of Revelation 13, it is listed as a separate identity from either the Rev. 13:1-2 Sea Beast or the Rev. 17 Scarlet Beast. The Land Beast worked in collusion with the Roman phase of the Sea Beast and under the direct eyesight of that Sea Beast (Rev. 13:14). That made them contemporaries of each other at that point.
John (and the rest of scripture) commonly used the word "Land" or "earth" (tes ges) to speak of "the land of Israel" - the promised land. This Rev. 13:11 "Beast from the land" with its two-horned power structure was connected with the land of Israel and its Pharisee / Sadducee religious leadership. That religious leadership in Jerusalem had turned into a "harlot" and had prostituted itself by aligning with Rome in order to preserve "their place and their nation", as Caiphas once said. There was a definite financial advantage to the priesthood and the Sanhedrin rulers in currying favor with Rome in order to keep the money flowing into their own pockets. Follow the money.
Concerning the identity of the dragon, you pretty much made my case. Satan used Herod, but Herod was the puppet of Rome, under its authority, so it was Rome that tried to devour the “man child, who was to rule all nations with a rod of iron: and her child was caught up unto God, and to his throne.” The dragon in 12 and 13 is clearly an illustration of pagan Rome. There is no evading it when versed in history and scripture.
As to the issue of imminence, read Zephaniah,
Hold thy peace at the presence of the Lord GOD: for the day of the LORD is at hand… (Zephaniah 1:7)
Zephaniah is proclaiming the imminent judgment of Judah at the hands of Babylon. He continues in Chapter 3,
Woe to her that is filthy and polluted, to the oppressing city! (Zephaniah 3:1)
Then “in that day” God relents and restores his people,
In that day shalt thou not be ashamed for all thy doings, wherein thou hast transgressed against me: for then I will take away out of the midst of thee them that rejoice in thy pride, and thou shalt no more be haughty because of my holy mountain… The remnant of Israel shall not do iniquity, nor speak lies; neither shall a deceitful tongue be found in their mouth: for they shall feed and lie down, and none shall make them afraid. (Zephaniah 3:11, 13)
Scripture supports the hermeneutic of imminence, which conflates near and far phenomena in prophecy without disclosure of the protracted time in between to promote vigilance and thwart lethargy.
As to the seven kings, the Persian empire was a blend of the previous Chaldean, as the Greek was a blend of the previous two, and the Roman was no different in this respect. How it was different is obvious; Daniel says it was different because of the ten horns (verse 7). Your failure, and neglect of history, to connect the horns with the ten toes are your undoing. As stated to Douggggg, the little horn is a beast/kingdom, revealed in Daniel 7 verses 8, 11, and 23, and represents the sea beast in power and renamed the scarlet beast when it’s wounded, and then cast into the lake of fire in Revelation 19:20. My take on the seven kings surpasses your poor view, because it is simple, if one does not neglect history.
The seven kings are Babylon, Persia, Greece, Rome, and the fifth, the papacy, illustrated as the sea beast. As to the sixth, the beast from the earth, it is a kingdom that wounds the sea beast, or at least supplants it as a secular world power that changes and makes an image to the first, establishing religion again as the seventh king.