What are the pros/cons of airlines selling tickets on a futures market?

Seems very complicated and convoluted without adding any value

The airlines already do a very thorough job themselves of optimizing the revenue from there existing capacity by deploying dynamic pricing based on supply and demand.
It's a pretty low margin business, so adding any type extra middle layer that also needs to be paid will add cost and raise prices. This wouldn't be competitive as compared to the direct model.
You can only swap a 737 for an RJ if you have a spare 737 standing around with nothing else to do. That's simply not the case. Airlines manage their fleet and staff very carefully to minimize down time. Less people fly on Wednesday then on Monday or Fridays, but it's impractical for the airlines to ground a few planes on Wednesdays.

Hilmar 85773

Source: stackoverflow.com