I would like Venom to have a deeper, softer voice, with a sinister feel to it.

Venom has a calm and unobtrusive personality—unless he perceives Zato to be in any sort of danger—as well as a literary mind. Having grown up in an impersonal environment from an early age, he doesn't have a particular sense of purpose in his life other than serving Zato and, by extension, the guild. Though Venom hates murder intuitively, he is a diligent person who will complete his assigned task regardless of his own desires. If not on a mission, he seems to prefer to intimidate his opponents via words rather than force a confrontation.