I primarily drive on 2WD as well.
When weather gets bad I drop it in auto for the added safety. I also believe that you should run it in auto for a few miles (in the correct weather) to let the fluids run through in the system.

 

I do the same.

 

With this vehicle, you should definitely be in 2WD almost all the time.
AWD uses more fuel and wears down components faster. AWD mode, engages the front differential and put the transfer actuator/clutch in a ready state that is NOT fully disengaged like it is in 2WD mode. Therefore you get some accelerated clutch/component/fluid wear compared to 2WD.
So I use it in snow for sure, freezing rain, off-road (like a campground, grass parking lot at a fair/festival, driving through the yard) and maybe rain.

 

Does everyone elses car make more noise in auto vs 2wd?

 

Mine does.

 

is there a concern for changing modes while driving? the wife switched up the modes while she was driving (under 50mph)

 

No concern.

 

This statement was copied from 2017 Owners Manual. More or less vehicle will shift transfer case when speed is correct so operator can adjust speed for engagement. This is when 4WD Low is requested.


4WD SHIFT IN PROGRESS This message will display while the four-wheel-drive system is shifting. FOR 4WD LOW SHIFT TO NEUTRAL If a four-wheel drive shift into 4 n is requested, and the vehicle speed is correct, but the transmission is not in N (Neutral), this message will display until the transmission is shifted to N (Neutral). FOR 4WD LOW SLOW TO XXX If a four-wheel drive shift into 4 n is requested, but the vehicle speed is too high, this message will display until the correct vehicle speed is reached.