What kind of car are you running? Is it not physically possible to change the inner pivot of the lower arm seperately from the upper link? I can't imagine a car designed like that but at any rate...
If you move both the upper and lower inner pivots up or down your roll center is being moved in the same direction. Both up - RC up; Both down - RC down.
This is because the IC is being moved in the same direction as you move both inner pivots and the RC location is determined by the IC as it relates to the contact point of the tire and where that connection crosses the vertical centerline of the car.
I'm no pro at tuning so I'm not going to speculate too much on what you might need in your car. I understand theory more than I understand reality.
I would start out by removing any shims you may have and find the best spring combo that give you a decent balance. Run a fairly standard setup like front toe even up and 3* toe at the back. I dont' know a good reason to change front toe just because grip is low. Taking toe out of the front is just going to make steering response slower and give you less steering because you're on a tight track. You need the wheels to turn so just keep em straight up I'd say.
What kind of camber are you running? Too much is no good because there may not be enough traction at the inside of the tire to get it to roll over and create a larger patch. You may want to stay conservative there... maybe like 1.5* ?