Do you believe ALL believers must "die" (necessitating a "resurrection") BEFORE He comes/returns/His Second Coming? (since "death" is totally defeated at that time [according to your understanding of 1Cor15:24, not mine 
], and it seems you are suggesting that in order for it to be "defeated" it must have been "experienced" [/actualized] in time/history, at some point, for any and all believers)
My view, as you may recall, is that "[bodily] resurrection [from the dead]" will not be experienced by those not having actually DIED, and that "resurrection" (except for those passages referring to "Israel" coming up out of the "graveyard of nations"--so not being 'a bodily resurrection from being formerly-physically dead,' there) ['resurrection'] means "to stand again [on the earth]" and pertains to "formerly-physically-DEAD" people [/saints, in the "resurrection OF LIFE" of course]; yet 1Cor15:51-54 is saying that both "the DEAD IN Christ," AND the "we [in Christ] which are ALIVE and remain unto" is who [in this "I tell you a mystery" section] that this "death is swallowed up in victory" applies to [not that it is the only (singular) point in time that "bodily resurrection from being formerly-dead" will take place, in the chronology that is revealed in Scripture], meaning, both of the "still-ALIVE" and the "having-previously-DIED" believers. [2Cor5:3-4 is speaking SOLELY of those "STILL-ALIVE" portion of "the Church which is His body [/believers]" as THAT is the focus of Paul's thought in those 2 verses]
As far as it not being the ONLY point-in-time of the chronology laid out in Scripture, I ask you to consider a post I made some time back (in the context of a different convo), essentially making two points about the "ORDER/SEQUENCE" of "resurrection" (meaning, that there doesn't remain only ONE)...
Consider:
[quoting my old post]
"[again, my viewpoint: "[re: resurrection] but each [G1538 - Hekastos - [defined as-->] 'each (of more than two)'] IN HIS OWN ORDER" 1Cor15:23; "blessed and holy is the one having A PART [G3313 - meros] in the first resurrection" Rev20:6... that is, in "the resurrection OF LIFE" Jn5:29--The 2W are included in this "resurrection OF LIFE" but are seen to be resurrected and ascended up to Heaven BEFORE the 7th Trumpet sounds (and so is "the Church which is His body" even earlier than that point in the chronology, which is what 1Cor15:51-54 is making a point to say, not to mention the "chronology/sequence" explanations found in passages such as 1Th and 2Th, and 2Tim4:8/Rev4:4/Rev5:9/Eph4:30, pertaining to same)]"
[end quoting my post]
There's more I could say, but this post is already long enough...
], and it seems you are suggesting that in order for it to be "defeated" it must have been "experienced" [/actualized] in time/history, at some point, for any and all believers)My view, as you may recall, is that "[bodily] resurrection [from the dead]" will not be experienced by those not having actually DIED, and that "resurrection" (except for those passages referring to "Israel" coming up out of the "graveyard of nations"--so not being 'a bodily resurrection from being formerly-physically dead,' there) ['resurrection'] means "to stand again [on the earth]" and pertains to "formerly-physically-DEAD" people [/saints, in the "resurrection OF LIFE" of course]; yet 1Cor15:51-54 is saying that both "the DEAD IN Christ," AND the "we [in Christ] which are ALIVE and remain unto" is who [in this "I tell you a mystery" section] that this "death is swallowed up in victory" applies to [not that it is the only (singular) point in time that "bodily resurrection from being formerly-dead" will take place, in the chronology that is revealed in Scripture], meaning, both of the "still-ALIVE" and the "having-previously-DIED" believers. [2Cor5:3-4 is speaking SOLELY of those "STILL-ALIVE" portion of "the Church which is His body [/believers]" as THAT is the focus of Paul's thought in those 2 verses]
As far as it not being the ONLY point-in-time of the chronology laid out in Scripture, I ask you to consider a post I made some time back (in the context of a different convo), essentially making two points about the "ORDER/SEQUENCE" of "resurrection" (meaning, that there doesn't remain only ONE)...
Consider:
[quoting my old post]
"[again, my viewpoint: "[re: resurrection] but each [G1538 - Hekastos - [defined as-->] 'each (of more than two)'] IN HIS OWN ORDER" 1Cor15:23; "blessed and holy is the one having A PART [G3313 - meros] in the first resurrection" Rev20:6... that is, in "the resurrection OF LIFE" Jn5:29--The 2W are included in this "resurrection OF LIFE" but are seen to be resurrected and ascended up to Heaven BEFORE the 7th Trumpet sounds (and so is "the Church which is His body" even earlier than that point in the chronology, which is what 1Cor15:51-54 is making a point to say, not to mention the "chronology/sequence" explanations found in passages such as 1Th and 2Th, and 2Tim4:8/Rev4:4/Rev5:9/Eph4:30, pertaining to same)]"
[end quoting my post]
There's more I could say, but this post is already long enough...
Here's my point: death is defeated at the resurrection of believers, which occurs at Christ's return. If an individual is already dead, they will be resurrected and glorified. If an individual is alive, they will be glorified without a resurrection, because it isn't needed. There is no more death at this time, so a Millennial scenario where individuals die, such as with their final battle at the end of the Millennium, is absurd. Death is defeated when Christ is returned.
Regarding "first resurrection", I believe it is a parallel phrase with "second death". Either one experiences a resurrection to glory, which is connected with Jesus' resurrection and is not a separate resurrection (see Rom 6:1-14), or he experiences second death to dishonor. I don't think the phrase "first resurrection" means that there are multiple resurrections, although one might consider the "second death" to be a type of resurrection.
Some within the early church thought that the "first resurrection" related to regeneration, but my view is that it is related to Jesus' resurrection, and those united with him in faith share his glorious resurrection. The word "first" indicates this association with his resurrection, but also is a word-play on second-death. Resurrection is to life and glory, death is to separation from God.
Regarding the Scriptures you mentioned, I think that dispensationalist try hard to squeeze gaps to assert a Millennium between different events, and I don't agree with their exegesis. I see too many verses that show no gaps and a general resurrection/judgment in the gospels and epistles.
But, you guys believe what you want. It's not a salvation issue. I think it is a disjointed way of viewing Scripture, and it leads to endless prophetic speculations, complex charts, etcetera. If that's what floats your boat, go for it.
