New Story

So, me, being the crazy freak I am, got a totally awesome idea for a story and wrote until dawn and got out 6 chapters for this new story idea. I know where I want to go with it, but I also don't want to disappoint anyone by adding another story to my 4 running stories. ASTLSTSWH will be finished by 20 chapters, RAH by 30-35 and SOD by about 25, same as its prequel, but it's getting strenuous having so much to update. I am doing the best I can...

Please tell me whether I should write the idea and sacrifice writing time for some of my other stories, or or finish those up and keep typing a little bit for this new story so once a few of those are done i can post the new story?

HELP!!!!????!!!!