Reply to Improving sound quality

I've been djing for about a year and a half and in the last two months purchased ableton suite and have been addicted to it ever since. The only problem I'm currently running into is that I've been producing with my 2012 macbook and hdj-2000s plugged directly to the built in soundcard. And when I listen to what I've created out other speakers it never sounds as good.

I'm currently looking for either an audio interface or some different headphones. What exactly would make the most difference? I've been looking into getting some open back headphones but will that really make that much of a difference?