I feel as though Toriyama-san intentionally (or unknowingly) crafted Vegeta’s Majin transformation in the Buu Saga to be a subtle metaphor for a person undergoing a midlife crisis.
Think about it, in Vegeta’s “bachelor” days, he was a ruthless-than-average Saiyan who killed beings and conquered planets without a care in the world. His experiences in both the Saiyan and Frieza Sagas started to changed his worldview and himself, and despite himself, he eventually settled down, got married and grew to become a father. But deep down, he longed for the “glory” days when he was someone obsessed with power, pride, and being #1, especially greater than Goku, hence the reason he sold his soul to Babidi. His mid-battle talks w/ Goku have him try to convince himself that he wants to live that “bachelor” life again, but even they both know that things aren’t the same as before; that the cold-blooded, merciless things he did before that fateful first trip to Earth can’t be revisited, and that somewhere deep down, Vegeta feels disgusted with the person he used to be serving under Frieza.
I don’t know if Toriyama planned it this way, but it’s that kind of a clever metaphor that fits right in with his Redemption arc, from his emotional Final Explosion sacrifice to his later resurrection as a redeemed soul.
What do you all think?