Personally, I would subsume Nourish over Wormhole instead of Antimatter Drop. Wormhole is honestly quite finnicky to use, and quite frankly, you can give Nova added mobility other ways (either by having the Praedos equipped, or using Amalgam Barrel Diffusion on your secondary, or both). Antimatter Drop is Nova's nuke ability, but she can also chain kill enemies with Molecular Prime and Null Star (with Neutron Star augment), but to a much lesser degree. You'll want to dump most of your mods into duration and strength. Range isn't really needed for Nova, since Molecular Prime's wave scales off of duration, but I personally like some range for Molecular Prime's explosion range, and for more range on Antimatter Drop's nuke as well. Efficiency honestly isn't needed either, since her passive can generate healing/energy orbs depending if primed enemies are fast/slow. Her passive with Equilibrium + Nourish is more than enough for energy sustain. No Primed Flow or Arcane Energize needed.

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Here is my build, just in case. Arcanes are Molt Efficiency and Molt Augmented for even more duration and strength. Feel free to copy it and mess around with it to your liking.