A few points where we are in agreement...
-The millennium is a literal thousand years.
-The general timespan of 7,000 years of mankind's history on this planet is somehow reflective of the 7 days of Creation week.
-A "long season" is defined by the wilderness wanderings as 40 years, and therefore, a "little season" (of Satan's release) is less than that.
Some of the notable disagreements...
-A proposed thousand-year limitation to Christ's reign contradicts Daniel's prediction that the "stone" kingdom established by Christ will last forever. It was Satan's deception that had the time limitation put on it - not Christ.
-The proposed 7-year time limitation for the Great Tribulation is not correct, since it would only be 42 months in which the city of Jerusalem and its sanctuary would be trodden underfoot after the city was first surrounded by armies (Luke 21:20's "abomination of desolation" which began the Great Tribulation).
-The millennium is not in the future, but in the past, since the Rev. 20 millennium ends with the First Resurrection (which was "Christ the First-fruits" along with the Matthew 27:52-53 resurrected saints who were also the same as the 144,000 "First-fruits unto God and the Lamb").
-Satan's release for that "little season" is not in the future either, but is also in the past, at the end of the Revelation 20 millennium which finished in AD 33, because John wrote that Satan had already come down to the earth for a "short time" in great wrath at the time he was writing Revelation.
-And a few more...
I appreciate anybody's labors to make sense of the numbers in scripture. But considering that God tends to hide things from the wise and prudent and reveal them unto babes, I'm thinking that perhaps God has actually hidden things in plain sight so that even the simplest mind can recognize and comprehend His purposes. Multiple layers of mathematical calculations would then be an unnecessary complication.