We have a 2017 XLT with the 2.3 EB and it idles right around 700-750 rpm. It is very smooth and quiet at idle whether in park/neutral or in gear, even with accessories running such as the AC or defroster, still very smooth. Maybe you have an air leak that's causing problems. Also check on the timing chain cover, they tend to leak I heard, ours did. We caught it at 44,000 miles so we were still in the power train warranty of 60,000 miles. It's an expensive repair if you have to pay for it yourself.
Whimsey