Smoke ring looks really good to me, same for juiciness, if you are using a home made rub with white sugar, change
the white sugar out for turbinado sugar which has a higher heat tolerance which means less burning of the sugars.
If you sauced the ribs maybe wait until the last 10 or 15 minutes of the cook to slather them up..
It all depends on the temp yer cooker is running at.