well now, night lords is merely just another name for a chapter is it not?
i mean, back in the old dex they had their own rules but now only the four main "heavy" per se (khorne berserkers, plague marines, 1k sons, noise marines) get special rules.so theers not actually a proper NL army now.
as to tactics, im not sure, im assuming you wanna play fluff style? so im not sure on that either, but wernt night lords like a "fast" force, attacking at night etc, so theyd maybe use a good few raptors and stuff like that?
sorry if this was actually no use to you lol, i just thought id contribute my little bit.
thanx ^^