The crucial flaw in all your theories is assuming Ciro was the Target. In reality all Siblings were deliberately misled, and the Target was Oric all along. You see, Oric has been trying to kill himself since before Time began, but his +10/+10 Awesome stat prevents him from doing something so lame and retarded. The cycle system is an attempt to force the RNG to turn Ciro into a character than can drain Class Stats, allowing Oric to finally jump off a high cliff and embrace sweet, sweet oblivion. The crucial flaw in Oric's plan is that he will have forgotten to dismantle the sissy revival machines, and despite killing every other Sibling over the course of his plan, he will have left alive Slog, unnoticed but all-loving, who will proceed to revive Oric, only this time as a girl because the Al's First Law of Revivification is that all lifeforms seek their femalest gender state. Also Al will be revived because he is this story's official Mary Sue and add Femoric, or possible Orica, to his harem. Al will then escape the Warrens, only to discover outside the Warrens is just more Warrens, and all of his flashbacks were actually made-up hallucinations stemming from never eating or drinking, I mean who the fuck told you only drinking blood was a good idea you dehydrated moron. Finally admitting defeat, Al sheds a single manly tear, but luckily Orica is there for him, and they embrace, but it turns out Orica was Al all along, and Al was Slog.
That, gentlemen, is why Oric wants to kill the target.