I read a lot on here before buying wheels and tires but never found exactly what I needed, so I thought I'd post my results for someone in the future.
I didn't want 20x10s because they stick out so far and because the tires always seem to rub. I did wanted to get out from under the wheel well a LITTLE, but was limited in wheels that I liked and available offset. Decided to go 20x9 +1mm offset.
For tires I wanted wider, and a little taller, but wasn't obsessed with max height. I don't like when tires are stuffed inside, and I HATE when tires rub. Why spend $50k and then have tires grinding into plastic or worse yet, cut your truck up to clear tires? Ended up going 295/55-20 BFG ATs. I could have possibly run 295/60s, but was not willing to risk rubbing and no returns once mounted. I've seen others run 295/60, but not on a +1 offset. Now that I have these in there, going 295/60 with this offset would have likely rubbed. 285/60 was also an option, but quite a bit more expensive and like I said, I cared more about width than height.
End results are great. No rub and has about 1/2" clearance at full lock leaving room for articulation off road with no run. The +1 offset left plenty of room for the upper control arm. Tires are about 1/2" outside fenders.
Mileage took a hit with these heavy ass tires, but I'm pretty happy with the look. For reference, this is a stock 2019 AT4 with a rough country front level kit.