Your original list with some corrections.
15.Barrett > Willemse
Barret is good under the high ball, but while solid on attack, he hardly sets the world alight.
Willemse had a slow start to test rugby and only recently is realising his potential. He is a better attacking player and has the potential to be the better long-term player.
50/50 at this stage, but tomorrow will be clearer who is currently the better player.
14.Jordan > Arendse
Both offer raw pace, but not much else when compared to world-class wingers.
Jordan is the more established player. If he gets space he is dangerous, but if he is closed down he offers little to nothin.
Jordan
13. Ioane > Am
Ioane was a great winger, perhaps the form winger in world rugby about 4 years ago.
but he lost form. Now he is moved to outside centre where he has been solid at best.
AM is the better playmaker with a good pass and with solid all-round game. If anything, he does not get enough opportunity on attack
AM gets the edge as a specialist outside Center.
12.Havili > De Allende
Delande is the better player. Havilli has done little at test level - yet. Although he has been in the worst ABS team of all time.
Delande
11.Clarke > Mapompi
Mapimpi is the best opportunist in world rugby. If he gets space he scores. Clarke may have a more allround game, but like Havilli he has not done much for the All Blacks so far.
Mapimpi
10.Barrett > Dullard
Barrett is the better player, but he has not been in top form this season. It is debatable if he is starting to be past his best.
Barrett.
09.Smith > Faffy Fucked
Smith was the better player, but might be passed his best. Faff has been too inconsistent in recent years.
Smith
08.Savea > Wiese
Savea. Although Savea is average behind a losing pack.
07.Cane > Du Toit
DuToit is the world player of the year. Same Cane is not even a test level player.
DuToit has not been in form so far this year, but he will get better as the season progresses- maybe tomorrow.
06.Ioane > Kolisi
Ioane is another player that has not really shown himself to be a standout at international level
Unlike Kolisi who has won the man of the match etc.
Kolisi
05.Barrett > De Jager
Barret is not a test standard player.
De Jager
04.Etzebeth > Whitelock
Whitelock is past his best.
Eztebeth
03.Malherbe > Ta'avoa
Malherbe easily.
02.Marx > Taukei’aho
Marx easily
01.Bower > Nyakane
I have not seen much of Bower yet. Ox Nche should be starting,
Nyakana should be a bench option to cover both sides of the scrum
50/50
Man for man, the Boks are better.