What makes a kit an ultra rare (in your opinion)?

The insane weapons passive makes the exemplar insane.
-. 15% power damage/force
--. 30% power effect duration
---. tech combos prime enemies for tech combos
----a. 35% power/force
b. 35% recharge speed, +1 power cell
-----a. 50% power effect duration, tech combo damage area lasts 50% longer
b. 25% power damage to shields, 50% combo damage
------a. deal 150 damage to nearby enemies every 10 seconds, *2 to shields, *1.5 to synthetics, primes for tech combos
b. Killing enemies with a combo gives 50% recharge speed.

And he has bio-electric defense. Which is one of the best passives for defense, giving 80 dr for the first 5 seconds of any fight, and has a recharge speed evolution.
And his melee uses the kett carfalon, restoring ~15-20% of his health per hit in a wide circle around him.

I have him at 1/1/1/6/6 and he is nuts, you don't even need to level his powers to rip everything to shreds while being a hearty tank, as he has both health and shield restoration, energy drain on a ~2-6 second cooldown and melee that heals him. The only weakness he has is that it takes a while to combo down lone enemies, but groups disappear in a chain of lightning.