I am a lvl 20 W/N myself and there have been many good suggestions already, but there are one more witch I always bring. Parasitic bond I find very usefull if used properly, and it only cost 5 mana. Gives enemy healthdegen of -1 for 20 sec. and you gain 30-102 health after 20sec or if enemy dies. Fast to cast (1 sec.) and fast recharge (2 sec.) If you have high strenght you can combine it with endure pain and get a wery nice self-healing and stamina package :) With 11 strenght and 7 curses I get temporary about 230 extra health from endure pain and 72 health per. parasitic bond. A nice deal if you ask me.