I think Frequent Flyer did a good job with the point valuation, but one thing that adds or reduces value of the points is also how easy/hard it is to get the points.

For Ex: My trading value for Delta is 1.1 cents just because it was very easy to transfer to friends and family for 1.1 cents all last year. Most on FT will also agree that they dont transfer MR straight to Delta unless there is a 40%~66% bonus promo which happened often last year as well.