I'm not a mod, so stating a personal and subjective opinion:
Let's suppose for argument's sake that unanswered questions get shown by default:
If someone (anyone) answers any question, it would disappear from that screen, right? Even when answered by rep 1 users, or users with highly upvoted questions, but no answers or drunk users, or... and then it'd never show up again...
However, with the "hot" questions you get best of both worlds: the questions that are freshly posted and the ones that get freshly edited and the ones freshly answered so you can dig in and give an even better answer then the existing one.
However, if you want, just make the "new" questions your personal home page on AU and then you have what you like, but I like the default best...
#;-)