Bernie doesn't really think everyone needs to pay more taxes. He wants to soak the rich, and especially the super-rich. That seems reasonable to me. We didn't do badly during the Eisenhower administration, when the highest tax rate was 90%. I don't think even Bernie would propose a return to those levels.
Bernie's actually a good speaker. And obviously he's far more knowledgeable than Trump about actual issues. But then that's true of nearly all the other candidates, except perhaps for Ben Carson. Electing Trump would, I think, be a very dangerous roll of the dice. He says he'd be "unpredictable" as president. That could turn out to be even more upsetting to his supporters than to his detractors.