Assassin/Ninja Lv 105 Build for Assassin (duos with Fallen Warrior)

I'm level 103 right now and duo with a level 105 Fallen Warrior. I don't have a specific build right now and open to revamping everything - would prefer a trickster/acrobat build tho. The warrior has two main builds: one focused on spell spam (mana regen/steal and spell damage) and the other one focused on melee (high DPS). What kind of aspects should I focus on?

Open to everything but definitely would prefer something not too expensive with Fruma coming up.