I have been playing as Korath for a while now in 3D. One thing I feel I have to report is that IMHO the Dark Influence building is way overpowered. A 100% bonus would still be enough to make the building worthwhile, but might not give the player quite so overwhelming influence at only one building per planet.

(For those who never tried Korath in TA: Dark Influence gives a 200% influence bonus and is a one per planet building)