The subject has been well covered many times and is difficult to answer well without specific information about the spending and redemption habits of the specific individuals involved. (Hint, provide more detail and we can be more helpful).

But in the interest of being helpful and bumping up my post count in the process, I'll suggest you look into hotel affinity cards - Starwood Amex for $30 a year with the first year free or the Hilton Amex or Visa. Also suggest you look into the Amtrak Visa. It allows transfers into Continental and has some good redemption on its own. Check them out on the Amtrak website.