I have 10k coupons and a 4-star Kakuzu (Earth Grudge Fear). I need some Advance Skill Trial Packs to breakthrough Kakuzu, so I think I should spending 10k coupons on Lucky Wheel with a chance to get Shisui Susanoo. Or should I spending coupons on Lucky Board to get 50 edo Itachi frags + 30 frags from Fukurokumaru's Deals?

This is my Kakuzu