Kicking this back up again...I took the car out last weekend for a longer drive than usual and definitely had a much rougher idle when coming off of the highway to a stop. My usual drives are about 6-8 miles in a loop around town with mostly lower speed (with squirts of power here and there), then a 2 mile or so highway stretch and back towards home on the 30-40 mph stop and go. This time, I stretched out a bit and took it about 15 miles down the highway (plus 5 miles to get there) with some harder bursts, but nothing crazy with too much traffic...once I got to my turnaround point, it was very rough at the stop light compared to normal. Still seems to have plenty of power and no CEL's at all, and settles back to normal with a little more local driving.

Looks like I'll need to run it out a bit to get to the true rough idle point and do some logging...I'd love to be comfortable taking this car on some longer trips, but not there yet for sure.