I started using zJyn lead again today in arena. Current team CLS, R2, Cassian and raid Han. I think it works decent. Here's why:
Stuns: Han, Jyn, R2, CLS. And if anyone is stunned, you can use Cassians special to apply that stun to someone who isn't (and all the other debuffs).
TM reduction: Jyn, Han, CLS
Cleanse: R2 (both zetas)
Revives: Jyn
Ability block: Cassian
AOE debuffs (to get exposes) Cassian, R2
Buff immunity: Cassian (basic), CLS
Not to mention buffs. R2 with stealth gets 5% protection recovery for the group and another 5% for the target. Han gives 15% protection on his special. Jyn gets 5% on her basic.
My Jyn is g10 and Cassian g11, so room for improvement. But overall I like all the ways to stop the other team.