Pence by far. I like what Trump had done from a policy perspective, but he has no self discipline and has the extraordinary to ability to alienate wealthy center right voters.
I will in fact concede that Trump's lack of self-discipline (and his preference for incompetent boobs like Rudy) is easily his greatest liability.
I think that's a symptom of a greater liability: he now relies on Fox News, lunatic fringe sites, and conspiracy theories originating on 4chan as his primary sources of information. This is your crackpot grandpa. And if advisors don't align with the kek-o-sphere, they get tossed out for someone who does.
That's how you end up with incompetent boobs like Rudy. They are either willing to go along with the lunatic fringe, or are fellow crackpot grandpas.
If Trump is losing, and can't listen to reason as far as how to right his campaign, going on ignorantly thinking the polls are fake news and he's heading for a landslide, he's going to dig himself one helluva hole. If I were a Republican, that would give me tremendous pause.