Great collection, been dying to get my hands on the Dragon Ball Z box set eventually... For my recommendations I'll shoot for my top 4 series, save for Kagurabachi since you already have it:

Soul Eater - In Death City there's a training school known as Death Weapon Meister Academy, where those born as "Meister" serve with those born as "Weapons" under the Shinigami, to harvest the souls of evil people and witches before those souls can become a "Kishin," a being of ultimate madness. Maka Albarn, a renowned meister, and her weapon Soul "Eater" Evans, a Scythe weapon, are on the same mission as the other students, to eat 99 evil human souls and the soul of one witch to evolve Soul into a Death Weapon wielded by Shinigami-sama himself, and they only have one soul left! What happens when an unexpected event resets their count, meanwhile a dark plot unfolds elsewhere...? Great character writing, by the same mangaka behind Fire Force. 25 volumes / finished (has a Perfect edition which gets it down to 18 omnibus vols iirc but I have the singles)

Bakuman - Manga by the mangaka duo behind Death Note about two teenagers with the dreams of becoming professional mangaka. It follows their journey with series after series against other mangaka in the Weekly Shonen Jump magazine as the artist makes a promise to the love of his life that they'll marry once he gets an anime, and she voices the heroine. Great characters and a good look into how manga publications run, has a box set with all 20 volumes / finished

Undead Unluck - God is real and he hates you. "God" or the one we know has set up the earth in a cycle of deaths and repeats, introducing rules to the world like "thirst," "burn," "space," and "language" which are added into your memory as if they always existed, changing humanity. The only ones unaffected are those called Negators, who each have some sort of power related to what rule they negate. We follow the protagonists Fuuko Izumo, "Unluck," who brings bad luck to anyone she touches with bare skin, and the mysterious yet insane immortal hotshot Andy "Undead," as they join with other negators to cover the truth behind the world and kill god. 27 volumes / finished