My impression - and I may be wrong - is that one of the reasons to join a writer's group was to get help with adhering to the "rules of publication." The vast majority of romance novels being published today -- at least the ones I see -- are "category romance novels", for which there's a very definite "formula" to the style of story being written. It doesn't mean that you have to stop being unique to make it as a writer, it just means that you are likely going to be marketing your work in a possibly more difficult arena.