Trump isn't a politician and you're right, didn't prepare like one. He's been travelling all over the country giving the same speech over and over again. It looks like he tried to essentially give the same talking points last night, while taking a few shots at Clinton. That strategy isn't going to work.
If he's going to try and play that strategy, he's going to have to REALLY get in the mud and sling all of Hilary's dirt out. If he's going to try and stay above the belt and focus on the issues, he has to actually focus on the issues.
Hilary just needs to be a solid politician and she should easily win the election.
When it came to the emails vs the tax return, I think she was full of it, but it's so much more presidential to say "I'm Sorry" and move on. Yeah, none of us think she was sorry, but it scored points with people who don't really follow the story. His answers on the tax return were ok, but he didn't do himself any favors. He should have made the point that a smart person tries to figure out how to pay as little income tax as possible (something that's ridiculous to ridicule him for) but he left that point to be made as a quippy retort while talking over her...
Overall, she won the night. It will be interesting to see if he was holding back to see the damage and will turn things up another notch or two or just try to roll with his current strategy which looks like it will fall short.