In previous years, there was a smoking side of Cassava Terrace, and the outdoor portion of Heliconia was smoking.
When we were at CN in December, there was no smoking in any of the restaurants, both indoor and outdoor. This was a change from previous years.
That said, there are tables directly outside the outdoor restaurants, and people regularly smoked at them. Depending on which way the breeze blows, you'll get the smoke if you sit along the outside.
Can't help you with the bars - we're usually too wiped out to stay up late!
You'll love CN if you're looking for a relaxing, non-glitzy resort that keeps with the laid back vibe of the island. It's very compact, and laid out nicely. Not a long walk to anywhere, and it's small enough that you run into the same people, and get to know them.
I think all of the restaurants are non-smoking now. The only one I'm uncertain about is the Beach Grill during the day. At the others--Cassava Terrace (the main dining room), Otaheite, Lychee, and Heliconia (the Beach Grill at night)--there is no smoking. At least that was the policy when we were last there in April 2011.
I know everything, and I'm always right (just ask my husband).
So have they changed policies at CSA or CSS about smoking in outdoor areas of restaurants. Just at CSA in Jan and still smoking at Palms, Sea Grapes and the Grill. Patior has always been all non-smoking as is Lemongrass and Feathers.