Now this is a decent argument and I appreciate you taking the time to look at the history of the manuscripts, although you have a few things wrong.
First, you don't have a source. In fact, you have manuscripts that do not have the KJV version eudokia with no sigma, of Luke 2:14, but you have also missed others that do have it.
Second, my source is The Greek New Testament 4th Edition by United Bible Societies, just so you know.
Third, the manuscripts below contain the preferred reading, which is eudokias, with the sigma at the end of the word, making it the genitive. God's favour is not the subject of the sentence as in the variation the later texts use, but it is something that could be said to be the OF God (genitive). In other words, the pleasure OF God, is on those people who believe, not some nebulous potential to believe. Otherwise, you have to throw out Scriptures like Eph. 1:4-5, that God not only predestined us, and predestined us before the foundation of the world.
"For He chose us in Him, before the foundation of the world, to be holy and blameless in His sight. In love 5 He predestined us to be adopted through Jesus Christ for Himself, according to His favor and will," Eph. 1:4-5
In other words, God knew long before the angels sang this at the birth of Christ, who had been chosen and predestined before the foundation of the world. His pleasure was on those he had chosen, not a lot of miserable sinners who would never be saved!
א A B D W it vig cop and early church fathers are Origen, Cyril Jerusalem, Gaudentius, Jerome, Augustie, Irenaeus, Athanasius, Hilary Ambrosiaster. Keep in mind "the most manuscripts," especially if they are just more of the same Byzantine tradition, does not make it the best reading!
UBS says that eudoias is the better reading, and in fact it is CERTAIN that eudokias in the Genitive is the right reading. Why, besides the fact that that eudokia, in the nominative is theologically incorrect? Well, because the better reading comes out of the earlier manuscripts, because there was less time for scribes to drop off a sigma, and so forth.
Eudokias
א aleph IV - (century)
B IV
D IV
W IV
Eudokia
E V!
G !X
H VI
K IX
L VIII
M ?
P IX
S ?
U ?
V ?
Gamma ?
Delta IX
Theta IX
Lambda ?
Xi
Psi IX/X
Y VI
Omega ?
Some of the above texts are so insignificant, they do not even rate a mention in the UBS Unical manuscripts. In any case, the earliest manuscripts and the most reliable, dating back to the 4th Century AD, all use eudokias, or the Genitive
The eudokia in the nominative, are in mostly 9th and 10th century texts, with three 6th century manuscripts.
So, which is better, a manuscript dated to less than 400 years after Jesus died,and after the book of Luke was actually written, or add 2 to 5 more centuries, more time for all those bored scribes to make copying mistakes, handed down? It only really takes one scribe leaving off the sigma and then it being copied over and over, for it to be considered a copyist mistake, which is probably the case for all those much later manuscripts. In addition, if the 4th manuscripts have a sigma, they certainly did not add it to 9th and 10th manuscripts that would not even exist for 5 or 6 centuries!
Finally, I do agree with you, that there are no "men of good will." We are certainly all sinners, and all born rebels. BUT, that is not what the other versions say!
“Glory to God in the highest,
And on earth peace among men with whom He is pleased." NASB
"“Glory to God in the highest,
and on earth peace among those with whom he is pleased!” ESV
“Glory to God in the highest heaven,
and on earth peace to those on whom his favor rests.” NIV
"“Glory to God in the highest,
and on earth peace among people with whom he is pleased!” NET
Eudokia (feminine noun) has nothing to do with "good will" at all. It has to do with God's favour, or in whom he is pleased.
Bauer (BDAG)
1. State or condition of being kindly disposed
2. state of condition of being favoured, favour, good pleasure. It refers to people on whom divine favour rests.
3. desire, usually directed towards something that causes satisfaction or favour, wish, desire.
#2 is obviously what is being said in this verse, since God himself is pleased with these people, or favours them.
Other uses of this, include:
"he predestined us for adoption to sonship through Jesus Christ, in accordance with his pleasure and will—" Eph. 1:5
"And a voice came from heaven, “You are my beloved Son; with you I am well pleased.” Mark 1:11 (God to Jesus after his baptism!)
So, in fact, God's favour or pleasure rests solely on those he has predestined. Surely, even the shepherds who heard the angels sing this, understood this! Israel had been God's chosen people, and now, with the advent of the birth of Christ, all those God chose before the foundation of the world would receive the favour of a sovereign God, who had chosen a new people - believers in Christ.
Of course, this is a different theological debate. The fact is, the mistranslation contained in the later manuscripts, point directly to universalism.
"Glory to God in the highest, and on earth peace, good will toward men." Luke 2:14 KJV
There is no good will, or more correctly "favour" or "pleasure" with sinners. You have actually contradicted yourself, saying we are all born sinners, rebels, (and I agree!) and yet even though we are all wicked sinners, God bestowed his favour on the whole world? He was pleased with evil sinners? The only way that can happen, is that Jesus death on the cross made everyone in the world saved, regardless of what they believe, so he is pleased with them!
You can't have God being pleased with sinners. Either the whole world has to be saved, and therefore Christianity is universalism, or God only bestows his favour, or is pleased with those who believe in Christ. So which is it?
Therefore, the certain manuscript evidence, and the theological implications of universalism, indicate that the reading is definitely eudokias, in the genitive, and there is peace on earth among those whom [God] is pleased. Believers only!