All my points are into Stamina and Health. I use bow and 2 handed mace. Leveled up fighters guild and mages guild skill lines. AOE grind, easy peasy. Traps from Fighters Guild. AOE from Mages guild. Rest bow action.
PvP same thing. Traps, AOE, and Bow. If someone gets in my face, DK's of course because honestly they are the only ones who can close the gap, or sorc with unlimited blink....lets not go there, I bust out the mace and beat in some face. The bonus to armor reduction is only way to survive in PvP, because your NB abilities blow, or are pretty much useless. Now Snipe with your crit abilities is not to shabby can pull of some nice 1600 to 2500 crits, if lucky.
I can put down traps with mage and fighters guild that by time someone or something (PVE) reaches me they are popping potions or calling for a heal. Amazing. NOT!
I have all these cool azz skills in the NB skill line, but no points into them, except 10 or so. Siphon, Stealth, and I forget the other as I maxed them then shelved them.
So if you want to survive as a Night Blade roll another toon, or use your weapon skills and other guiild skills, because the ones you come with will just let you down in the long run. Not saying they need fixing, they just need to, well, one word, work.
But seriously if you are not doing well, there are plenty options to choose from. I may even respec and not put any points into my NB skills as honestly the other ones kick major ass. I only chose NB anyways too look cool, thats what its all about. If you dont look cool, you wont feel cool.