I actually think the perfect companion to a Yv-666 packing Zuckuss and 4-Lom or Gunner Bossk would be a Bumpmaster.

Bumpmaster:

Contact scout-

Intel agent

Anti persuit lasers

Feedback Array

Intimidation

You park that in front of an enemy, park the Yv-666 behind and have fun as everyone jams and your YV unleashes hell. You could even have a Greedo/Boba YV as well, two Yvs and a Bumpmaster is nothing to scoff at.

For 50pts, I've run Bossk with Calculation, Recon Spec, K-4 Droid, Greedo, and HLC. Hits like a freight train. If the dice are in your favour, you can push through 5 damage, including a face up card thanks to Greedo. Swats TLT Y-Wings like nobody's business.

Recently ran him with VI, Mangler, 4-LOM, Zuckuss and K-4 crews at 45pts. The synergy of 4-LOM and Zuckuss crew ruins high agility ships' day. In one salvo I dropped Vader to 1HP after denying him the use of his focus token and then taking 2 stress to get him to reroll his successful evades.