Edit 1: I tried your settings and its FUCKEN-AWE-SOME!?
Glad ya dig
I almost always just double track guitars, but some bands like to quad track, and for that, A different mic sim or whatever should be enough. But make sure that the two tracks panned at 75% have alot less distortion, and more of a cleaner sound. This is for note definition, especially if the two tracks panned at 100% have high amounts of distortion. I NEVER EVER have the same amount of gain on the tracks panned at 75% as I do on the tracks panned at 100%.
(It will also work if the tracks panned at 100% have less distortion while the tracks at 75% percent have more distortion, but in my opinion it doesnt sound as balanced as the other way around.)
And for faders-
Group the two tracks panned at 100% to one bus or Aux track. Adjust the volume of the single tracks until the left and right side of the fader on the Bus/Aux tracks are peaking at the same volume.
Then do the same for the two tracks panned at 75% and group to a different bus. Once you have that done, adjust the volume of the two bus or Aux tracks until they fit well with each other, and then for ease I group those two Busses to one single bus once the levels are adjusted.
And harmonies-
I almost always add two extra guitar tracks (one for each harmony obviously) panned at about 20% left and right, so during the harmonies there are a total of about 6 tracks of guitar in all playing back at once. This will not be a problem as long the rhythm tracks panned at 75% and 100% Left are doing the same and the tracks panned at 75% and 100% Right are doing the same thing. So in other words, the rhythms should only sound like 2 tracks at almost all times, despite being an actual of 4 tracks. But, sometimes I have the rhythm tracks doing the harmonies without any backing tracks and it sounds fine.
Hope this made sense