You're in luck. You have fantastic CB champs.

• Kyoku - Ally Protect + Block Damage. Amazing combo.
• Fayne - Debuffs + Poisons
• Brago - DEF up + ATK down
• Ghrush - Leech (turn off A2 and A3)
• Skullcrusher - CA + AP

i think about this 2 option 

1 -  kyoku, brago, skullcrusher, ghrush, ninja 

or 

2 - kyoku, brago, seeker, skullcrusher, ninja

what do you think?

What do I think? I think you should use the team I suggested you use :)

Ninja is very strong, yes, but you want the debuffs that Fayne brings. Without Fayne on the team, you lose a reliable DEF down, and you lose Weaken, along with the poisons. And without Ghrush, you lose leech, which you'll need to survive.