So a lot folks sleep on Dark. It's not as "Flashy" as Fire or Arsenal or whatever. They see some lower numbers it does. BUT, BUT!! We had chart somewhere on forums of extensive testing done. (I knew majority of that from live). But Negative Damage was 2nd or 3rd least resisted by mobs on average. Fire was first(at the time). Was either Cold and Negative or Negative and Cold, either way in top three. Factor in all utility debuffs and your a Kin so you'll be raising the damage anyways.
Controller (Darkness Control - Kinetics).mbd
As for Incarnates. So since you'll have a Endo heal you could take extra damage Alpha, though I'm still a huge fan of Cardiac even with an endo heal, lol. BUT, Barrier in my opinion is a must for this build. As for Interface, with Kin heal have a -Regen. You won't really need Diamagnetic(less you wanna stack Tohit debuffs more). So something Like Spectral or other damaging one can be handly.