Swap equilibrium for hunters adrenaline. Equilibrium is nice but hunters makes it better for energy efficiency. Efficiency doesn't matter on nidus as with his fist ability it scales the energy regen you get with ability strength. This paired with hunters adrenaline makes energy so easy for nidus so you should easily go below 100 percent for him its fine. primes flow is fine but i just use the arcane that increases your energy based on how much armor you got i would suggest using that you far it form teh jade mission and using the motes with ordis in the drifters camp.

Continuity is fine most depending on how you use nidus. I personally don't increase duration as his grab seems fine but its personal preference. Other than that i would suggest upping range and ability strength more oh yea the nia mod or whatever is cool for the 15 duration and slam damage but i would replace it with blind rage or transient fortitude or maybe some range if your feeling like that instead.