Okay, this particular question will come down to personal preference and what you feel is important in a relationship. For me, I think a power balance is important, and the ability to grow. That’s why I always say Jacob.

There is no balance in Bella’s relationship with Edward. Sure, they have a lot of chemistry, they clearly care very much about each other and it’s not like you get to choose who you fall for. But Bella doesn’t get to make her own decisions. Go down to La Push? Total the truck. Trying to go again? Have your sister watch her. Wants to go further? Hold her until she stops trying to undress even though you want it too. You see the problem. Bella’s lack of action in New Moon for the first few might be just that she’s gotten used to not making her own decisions. Jacob, however, is very easygoing at the start. Of course, once his wolf persona starts coming up, he changes, but he doesn’t make decisions for Bella. I mean, kissing a girl without her permission is disgusting, but he at least doesn’t physically stop her from doing anything. Even though he is very vocal about disapproving of Bella hanging out with vampires, he doesn’t actually try to keep her at La Push by totaling her vehicle or things like that.

As for the ability to grow…basically, vampires stop growing at all from the moment they’re turned. Their personality traits and maturity remain the same. It’s the reason why immortal children are so dangerous, and the thing is, if Edward can’t grow, Bella can’t grow either. And a healthy relationship does grow. The relationship literally holds her back. Jacob, while he doesn’t age yet, is still a lot more human. He can grow and develop in maturity. He just won’t age physically until he stops phasing. They could still grow up together and their relationship would grow and change with it.

That’s my two cents.