The question was "What is more desireable? " so I assume you mean to the general public. Most of these guys are answering from an owners perspective, which is going to be rather biased in favor of the truck they own.
From a NON 67-72 owner let me throw my opinion out there.
67-68 - "more desireable" for the custom crowd. When someone wants a truck to smooth out and lower this is the favorite style.
71-72- "more desireable" for the restored truck buyers. They had many of the options available that the later trucks offered, making them more desirable for the collector type owners.
69-70 "more desireable" for the average Joe truck owner. This good looking style gets skipped over by the other crowds leaving it for the guys that just want a good looking truck that can be used and/or abused.
Just "my" opinion, so let the flaming begin....
