I have BS A/T 265/70R16 and more negative offset mags. There was some improvement in the handling. The rear wallowing disappeared, most likely due to stiffer sidewalls of A/T tires. The drawback for bigger tires is slower acceleration and worse FC.
Sorry bro, I just couldn't relate to what you're experiencing. I have been to Ilocos Norte once, and Catbalogan, Samar 4x (really bad roads), with speeds sometimes reaching 120kph on some smooth stretches (actually, smooth is not smooth at all in provincial highways), and I couldn't seem to recall any lane changing behavior. Road surface kickback, yes, due to the rack-and-pinion steering, but not enough to cause instability.
Is this due to the 17" mags? Lesser tire sidewall height = lesser road vibration absorption, aggravated by relatively thin tires?
I'm just guessing here.....
Those mags are HOT!!!