I mentioned this to Ed but I have more data. I just backed the Maxima into my driveway and the car was very resistant to rolling in reverse. I had almost convinced myself it was a rear caliper hanging up. But it wasn't nearly as bad going forward. Only going in reverse. I did more experimenting and it turns out it has drag when I am in reverse GEAR. I did a quick test and rolled backward then popped it out of reverse. I heard a thud (gears disengaging) and the car rolled a lot more normally.
I still wonder if this is related to the startup idle issue where the transmission presents too much load to the engine. It's been cold recently so I'm sure that is a contributor.
The fluid may be low...I dunno. Maybe I'll plan to change it out for whatever that recommended Redline synthetic is that also supposedly helps engage 1st when cold.