The neg'var is a great ship but id like to see one with a lil bit more tactical layout. Since the sov got a wide arc torpedo it could have a wide arc dual heavy disruptor cannon 90 degree arc x2 acc mod. Same boff and console layout as the Sov +1. The negvar console could be a heavy barrage console that is similar to cannon rapid fire but instead increases all weapon fire rates by 20% and dmg by 10% for 10-15 seconds.
Give it the Reagent negvar skin from DS9, with the underslung cannons.