My Diners expires this month and I am wondering what kind of mileage bonus, if any, it would be reasonable to request to get me to renew. Since my Amex Centurion Card offers superior benefits for most purchases, the only thing I use my Diners Card for is rental car charges. My DC usage is therefore very low, so I am probably not one of their most favored customers. Any ideas what type of bonus might be reasonable for a low usage cardmember? Thanks!