1) Christian Romance - I can understand books that are centered around religion and I can understand books that are centered around romance, but with so many stipulations on the Christian religion and intimacy, I can't really see that sort of book being at all fulfilling. Instead of having main characters confess their love to their significant others you will see them praising God? I just can't see how these two genres would ever coexist well.
2) Diet - I am a woman. I diet. It is just a part of being of that particular gender. However, I am a firm believer in simply eating healthy and exercising. The gimmick diets don't impress me and when I read, I want to read for pleasure, not so I can feel bad about those extra 5-10 pounds.
4) Short Stories - This one is a bit iffy. I will read short stories if I have already gotten into the core series and loved it. Sometimes finding out little tidbits about my favorite characters that I couldn't learn from the original books is nice. But, I do not set out to read short stories. On Amazon, when I am on a 1-click bender, I won't even read the synopsis for books that are under 150 pages. I like long stories. Personal preference.