(The 4-Piece Glad's bonus is not actually Physical DMG Bonus%, but it's not relevant to this discussion as like you said Starsilver will be stronger anyway so I'll leave it out.)
Either way, I took out the 4-Piece Glad's bonus (just that, kept everything else) and here's what I got.
Aminus deals 2977 DMG.
Starsilver deals 3120 DMG.
I will agree with you here, that is a much clearer difference comparing to mine. So let's say Starsilver does have a considerable Physical DMG advantage over Aminus.
However, since I felt like it's still not enough to edge over the Electro DMG advantage that Aminus has, I decided to take some more calculations.
So, ignoring the Physical DMG Bonus stat:
Aminus deals (704 x 189.7%) + 311 = 1646 DMG
Starsilver deals (704 x 164.6%) + 311 = 1470 DMG
Using that, here's their Electro DMG (from the Skill and Burst):
Aminus:
Press E = 4592 DMG
Hold E = 6798 DMG
Starsilver:
Press E = 4101 DMG
Hold E = 6071 DMG
Upon Burst: 3293 DMG
The Wolf's auto-combo: 1976 DMG
So yeah, as I suspected, the Electro DMG advantage that Aminus has over Starsilver edges the Physical DMG advantage that Starsilver has over Aminus.
Also we're not counting the weapon procs, which Aminus is thrice stronger than Starsilver at R1. (I'm not counting Starsilver's 200% because Razor most of the time will remove the Cryo debuff because of Superconduct.)
Man that was long, I hope you're not thinking I'm mad at you for writing all this or anything, I'm just really curious to figure this entire thing out because I am a huge number geek :) I should also say I'm also not forcing people to use Aminus or anything, people can use whichever they want. The Starsilver looks cooler anyway :P