It also depends on what type of Nephilim list you want to run, personally I enjoy adding the Primordial Magic to Lilith (when I borrow her from one of my players), so I can have a starting hand size of 7, draw 1 because of her ability, and then discard 1 (again because of that ability). Gives you a better chance at getting a decent card into hand and getting rid of a bad one.
There are two main ways to run a Lilith list, you either take heavier and expensive minions like Lelus and Lilitus, maybe a Mature Nephilim and is more like your elite style of play. The other is a Growth list. Lilith where you take a smattering of smaller models and a few cheap living models, and generally a Black Blood Shaman to get more blood counters, and turn those smaller models like terror tots and young nephilim and turn them into big meaty Mature Nephilim.
I'd read this over to get a good grasp of your master:
http://pullmyfinger.wikispaces.com/Lilith