We were in a Courtyard Villa on Norwegian Jade in 2010. We enjoyed it a great deal. After touring all day, every day, in the Med, it was nice to get back to ship and unwind in the Courtyard pool, which we usually had to ourselves. There is also a generous amount of outdoor space one deck above -- although we didn't use it much as we went in early spring when temperatures were cool.
The cabin itself was marvelous (our category had two bedrooms), although you can get the same cabin layout without the Villa perks. (The suite perks will still come with it.)
If you can swing it, I'd say to go for the Villa accommodations. And, it's far more intimate on N. Jade than on N. Epic (as far as I can tell).
Happy to answer any additional questions.