Keep your focus. Either your target user group or the tasks that you define should be fairly tightly defined. There are of course exceptions to this, but being all things to all people usually results in doing most things in a mediocre fashion. Not everything needs to be a small, single-purpose tool (though cat(1) is indeed beautiful in its sense of purpose and its utility), but you'll do better with a firm list of what you want to do, and who you want to do it for.