Which Might and Magic universe are you referring to?

I don't think it's useful to compare them. Might and Magic was high-tech fantasy, and that was its, pardon, unique selling point. And Arcanum is a classic fantasy story. Comparing them is like comparing Warcraft and StarCraft: someone who doesn't know anything about them might think they're similar (but only visually). Ubisoft just bought the name, and since Van Caneghem refused to participate in the project, they had no choice but to create their own world and do whatever they wanted...