It's not the best board out there, but it's the one I've been on. The NS SL is a great beginner board IMO. Very damp, smooth and confidence building. The rocker wasn't too crazy (it was my first time on non-camber). It's a good board.
there are others out there.
159 is way big IMO. At your weight 150-154 sounds good.
Another board I recommend wholeheartedly is an Arbor Coda 153. Absolutely a blast to ride.