Lately for the past few years I've been focused on writing short stories. Now, after I came up with ideas that are too complex to fit into a short story, I decided I may write a novel (200 page story) Last time I attempted to write a novel, I ran out of ideas and it stopped at 50 pages into it. I never finished, and now looking back at it. It was kind of mediocre. Any tips or cues from those of you who have experience writing novels?