This is really two issues:
Dispensationalism vs a form of covenantalism
pre-trib vs post-trib
Historic pre mill is
both non-dispensational
and post-trib.
I hope you see that but I'm not sure you do, since you seem to be fully in agreement with a form of dispensationalism (a la MacArthur). So when you say you think historic premill may be a valid alternative, I think you may be referring
only to a post-trib dispensationalism, though I hope you are also open to abandoning dispensationalism.
Anyway...
Mostly I moved to historic pre mill when I saw that scripture in no way supports the dispensational system and then realized the scripture points to a single coming event, not a rapture and second coming separated by 7 years. Tom Butler is right, nothing in scripture unmistakably points to a pre trib gathering of the elect.
Since the dispensationalism horse is currently being beaten to death in a couple threads I'll just focus on the timing of the rapture:
The only view that makes sense of the scripture is a single post-trib rapture at the Second Coming.
1Th 4:15-17 HCSB - For we say this to you by a revelation from the Lord: We who are still alive at the Lord's coming will certainly have no advantage over those who have fallen asleep. For the Lord Himself will descend from heaven with a shout, with the archangel's voice, and with the trumpet of God, and the dead in Christ will rise first. Then we who are still alive will be caught up together with them in the clouds to meet the Lord in the air and so we will always be with the Lord.
Jesus returns and all the Christian dead are raised and the living believers are glorified together. The gospels, the epistles and Revelation all specify that the resurrection of believers is at the very end of the age, not seven years before the end. If pre-tribulationism is true then there must be multiple resurrections of believers, at least 2, one at the rapture then one again at the end of the tribulation. But we only see one resurrection for believers, at Christ's glorious appearing at the end of the age.
Also this does not say anything about what happens afterward except that we will never again be separated from the Lord. There is nothing here that explicitly says Jesus does or doesn't come to earth or return to Heaven, though the word used for "meet" referring to our meeting Christ in the air indicates that he continues to the earth with the believers escorting/accompanying him.
1Co 15:50-52 HCSB - Brothers, I tell you this: Flesh and blood cannot inherit the kingdom of God, and corruption cannot inherit incorruption. Listen! I am telling you a mystery: We will not all fall asleep, but we will all be changed, in a moment, in the blink of an eye, at the last trumpet. For the trumpet will sound, and the dead will be raised incorruptible, and we will be changed.
This return and our gathering to Christ occurs at the
last trumpet, not
a trumpet a couple years before 7 more trumpets.
Mat 24:29-31 HCSB - "Immediately after the tribulation of those days: The sun will be darkened, and the moon will not shed its light; the stars will fall from the sky, and the celestial powers will be shaken. "Then the sign of the Son of Man will appear in the sky, and then all the peoples of the earth will mourn; and they will see the Son of Man coming on the clouds of heaven with power and great glory. He will send out His angels with a loud trumpet, and they will gather His elect from the four winds, from one end of the sky to the other.
That's just obvious.
