For other upgrades, get the Generalist Upgrade deck. That will give you the wave 1 and 2 general Neverborn upgrades. The only other upgrade you'll be missing is Rapid Growth, which is in the Nephilim set, and the stuff from Ripples of Fate, which will be in the Generalist upgrade deck 2. They put Rapid Growth there since you can't really run a Growth list without those models. There's a few upgrades in there that help, like Wings of Darkness which gives her Flight and Rush of Magic for an additional card draw. Flight goes with her ability to declare actions without line of sight - she can charge through/over a building and get her bonus.
Really though it's all about playing her and figuring out how her actions work for you. She's got an upgrade for a Lure, though you can also get one with Lilutu which is a great model. She can root people which hampers movement and damages them if they're pushed out of it. Tangle Shadows is great with her ability that ignores LoS for actions. Try putting a beater in the opponents face that hasn't yet activated.
Wings of Darkness is pretty important though. Lilith is a guerrilla fighter, not a brawler. So having her ignore terrain with her Wk 6 and 3 actions is pretty big.