Kanzenshuu

Hit isn't playful like Goku and I could see Hit not respecting Zamasu ideology. I could see Hit just killing Zamasu because he doesn't come off as friendly or respectful. The playful nature of Goku is what angers someone like Zamasu in my opinion.

Cooler.

He just came off as Frieza's prodigious brother who did his own thing like an Itachi vibe. He would've fit nice in the actual universe.