I'm not sure what "supposed to sit how stock is from inside" means. It definitely won't be the same stance as stock wheels of any configuration. I don't know what your stock wheels are, but from a 20" SLT wheel (+27mm offset), a -1 will move your tire out a full inch. And if you're going for a large tire size, it may cause your tire to rub on the actually fender/wheel well edge where you have to trim metal, as opposed to just having to zip tie the liner.
I'm pretty confused here, too. Not sure what oversteer has to do with rubbing on UCAs or the sway bar. Who is giving you this info? If you are considering buying tires from them, I would go somewhere else.
You won't have issues rubbing with 305's if you go with the -1 offset. If you have SLT stock wheels and have a +27 offset (or similar), there's a high chance you'll rub with aluminum (or stamped steel) UCAs and 305 width. There are a lot of "OMG I'm rubbing with 305's on a 2.5" level - HELP" threads because it seems the cast steel UCAs have a bit more clearance than the stamped/Alum ones and the different UCAs aren't a common spec listed when people post their setup and claim no rubbing.
So... you want it all with no compromise? Gotcha [emoji6]
I would go with BFG K02s in your situation. I was basically had many of the same desires, but didn't care as much about the road noise so I went with the STT Pros. There are a lot of fans of different AT's and MT's here, but I place a good bit of important on winter performance without going to a straight snow tire. The K02's and the STT Pros stood out in my research, and I liked the look of the STT Pros despite the minor hum at higher speeds. Plus I have used the BFG's before and wanted to give the STT Pros a try.
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