What timing am I looking for at freeway cruising speed? Mine shows over 30 while cruising, and drops to under 20 degrees if I hammer it. Isn't that backwards?

While we're at it, what 02 sensor numbers are proper? I think mine are OK, but I'm curious. I wish they had a chart repository to look through.

LS6 engine, 212/218 558/563, truck accessories, stock manifolds w/ a 40 series, 373, HP Tuner Basic

I'm showing over 40 kPa at idle and 90 at 50% throttle