There are several other factors related to the physics of the situation which should be examined.

The longer the rod, the greater the force required of the angler to cast. Why? Because the line has a longer lever to "pull" against. OTOH, in fighting a fish, the longer rod gives the fish a greater leverage against the angler, making the fight greater. OTOH, (how many hands do you have?) netting a fish with a 10' rod, assuming you are as reluctant as I am to let the leader/line connection inside the tiptop, is very difficult and is best done by someone who either employs a gillie, or has but lately descended from the family tree and falls into the class of "knuckledragger".

Yet, I favor the 10' rod. In 1910, a rod as short as 10' was considered a "ladies rod". I've spent many days casting dry flies with a 10' wetfly rod ca. 1890. With the proper static balance I never found it wearing. All that said, for the last two seasons I've used a 7' 4wt Santos for everything ... go figure.

"Can't I, after all this, find at least one kind thing to say about our new short fly rods? Well, yes, perhaps this, I am reminded of the country sage's defense of bad breath. "It's mighty unpleasant, but it beats no breath at all."
from "Fly-fishing Heresies" by Leonard M. Wright (1975 - Winchester)

Best regards,
Reed