Fix all MAJOR bugs first. After that then work on the fun/interesting features that have been requested until you run out of fun/interesting ones. Then fix more bugs. Judge what you think would be more useful to the users. Also a voting system would be a pretty good idea. Just have a big list of features and have people upvote or downvote the ones they like or dislike respectively.
If you come across a feature that you are not particularly interested in, spice it up a bit yourself. Add your own flavor to it.
And when your bored of all of that, refactor!