Even at 21-22 mpg city is really good compared to my 17-18 of my 11 3.7L MDX. It could be the hybrid battery might not be charged enough to give you longer an EV mode? On a normal city drive, my hybrid battery can range from 1/4 to 3/4 in 5-15 minutes.
It would be a nice feature for the 4th Gen MDX sh-sh-awd to have a plug-in option to top off the hybrid battery. I see a lot of empty prime parking spots for plug-in vehicles only around town.
Son - 06 TSX 5AT w/ Navi, Carbon Gray w/ Quartz
08 RDX Tech, Moroccan Red Pearl w/ Taupe
11 MDX Adv/Ent, Palladium Metallic w/ Ebony
19 MDX sh-sh-awd Adv Fathom Blue Pearl w/ Graystone