What I would propose, assuming all abilities are maxed out:
Cruel Strike - Deals physical damage to target enemy, with a 100% chance to attack again.
- She dual wields, double attack reflects her offhand swing, gives her good synergy with things like Phasma
Strike Fear - Dispels all positive status effects from all enemies. For each effect dispelled this way, Asajj gains 7% health (no longer 40% baseline +7% per), and reduces her targets turn meter by 10% per effect dispelled (ex. 10 buffs removed = 100% turn meter reduction from her targeted enemy).
- It's called Strike Fear, but it's a self-heal, which isn't really scary - but losing your buffs and losing a turn is kind of scary?
Endless Wrath - Deal Special Damage to all enemies, resets her cooldowns on a finishing blow. (Unchanged)
- Endless wrath + Rampage is the keystone of her design, and probably deserves to be maintained
Nightsister Swiftness - Increases Nightsister speed by 26, and whenever a Nightsister deals damage they have an 18% chance to call another Nightsister to attack, for 15% reduced damage.
- So this is a variant on Phasma's Leader ability, to create a little more variety in the game. Unlike Phasma's version it doesn't proc off, or call for, non-Nightsisters (greatly limiting weird comps, and/or encouraging Nightsister teams). This turns the Nightsisters into a specialty high-synergy team, comparable to Droid teams.
Rampage - Whenever an enemy is defeated (no longer procs off ally deaths!), Asajj gains Offense Up and 50% turn meter.
- The critical chance up was a little bizarre, for someone with no crit synergy - more (consistent!) turn meter would feel way more like she's on a murderous rampage though! It would also help her Endless Wrath chains to feel a little more Endless... (rather than the one-time-thing they are currently, because she's dead before her next turn)
Summary: Her Cruel Strike works well in Phasma comps due to its consistent double attack (which is less than the chance of Rey/Leia triple attacks still, but it's something in that vein of synergy). Cruel Strike works especcially well when combined with Asajj's new Nightsister Swiftness Leader ability - which is an alternate version of Phasma's leader ability; but unique/limited to Nightsisters. Cruel Strike no longer stuns, but now it does more damage overall (since it attacks twice).
Strike Fear is a much less potent heal than it currently is (dispelling 5 buffs would be only a 35% heal, rather than the 75% heal it currently is) - but the TMR gives her a more unique ability to turn the flow of a fight on its head (dispelling buffs, self-healing a bit, and then denying someone half a turn, all at once).
Endless Wrath + Rampage synergy deals less burst damage (no Crit Chance up), and procs less often (doesn't proc on allied deaths anymore), but if you ignore Asajj and her team gets a kill, she quickly becomes a massive threat due to her 50% TM gains off each chain kill (and Offense up).
Nighsister Swiftness creates a new high-synergy specialty comp out of the Nightsisters, in which they can proc a lot of bonus assists - and becomes especcially potent once enemies start falling: due to Asajj's Rampage now granting consistent turn meter gains, and her Rampage / Cruel Strike granting frequent high chances of calling for assists (leading to more kills, leading to more Rampage).
In the meta, Asajj is still relatively slow, and the Nightsisters are still collectively pretty frail - so it makes sense to target Asajj early and try to burn her down before they can land a kill and set Asajj up to begin her Rampage.
Asajj isn't limited only to Nightsister teams though, her basic Rampage+Wrath combos, and her new Cruel Strike's double attack effect means she can work well as an alternate to Rey/Leia on a Phasma team (and, canonically, makes a lot more sense than stick-girl and non-combatant-sister/love interest being the most dangerous people in the universe).
Edit: Another thought - Ahsoka and Savage should both count as Nightsister and/or, Asajj should count as Sith?
