For me I think its the opposite.

Duke200 better for traffic since smaller in size, not the handlebar without balancer. Also lighter, easier to maneuver.
For the Duke390, its better for highway since topspeed already >160km/h, engine rev also no need so high, heavy = more stable. Got balancer also, no need vibrate so much.

First rule for recommendation is tell us your requirement. Then I can start judging from there.

Your workplace you pass by city/highway how many percent? But yeah, Duke200 more towards city riding. Cruising 100km/h no problem. But for highway so people might want to take it up to 140km/h and above.

My friend say NVH on Duke 390 is awesome wor

doesnt looks like it, i saw in shop still selling about RM20k for abs version duke 200
to be honest i agree after test ride 390, darn it but still love mah 200 

although kawa z250 also a naked bike, almost same price with 2 cylinder engine i only interested in duke

personal preferences, i think z250 kinda looks a bit unstable (design wise), tail kinda too small, but thats just me