I'm not sure if this helps, but my brother had to apply for a US visa in January this year. He didn't have a criminal record of any sort, but he had to apply cos he didn't qualify for the waiver.
Anyway, he told me that at the interview, in the 1hr he was there, about 10 ppl got rejected. Apparently it's like going to the RTA, so he could pretty much hear everything and a lot of them got rejected for not having the correct paperwork. His interview only lasted 15mins, he had everything he needed, proof of funds, letter from work, enrolment from uni, proof of ties to Australia etc... Also he noticed that it really depended on the officer that's interviewing you... he said there was this one guy who was rejecting like every single application he was reviewing!
His went through his interview without any problem. They asked him what his intentions were, where he was going, also to list all the countries he has visited before...and some questions about the holiday etc.. I guess they just wanted to sus out if he was genuine or not. He's 21...and the younger you are, it's a risk for them to let you through as there's a bigger chance you will stay there and never come back. They granted him a 10yr visa which was a nice surprise.
So I guess if you do intend to apply for a Visa, make sure you have all the correct paperwork, if they won't grant you a tourist visa, I doubt they will grant you a work visa.