Mk 13 Air Dropped Torpedo

I just finished the book "The Last Stand of the Tin Can Sailors" and it
raised some questions about the air dropped torpedoes (the Mk 13) in use by
the US Navy in WWII.

What drove the range/speed trade-offs for the Mk 13? According to the
spec's I've found, it had a range of ~6,000 yards and a speed of 33 knots.
With a likely launch range of 1,000 yards or less, wouldn't it have made
sense to sacrifice the 6,000 yard range to get an increase in speed?
Wouldn't a 45 or 50 knot torpedo with a 1,500 or 2,000 yard range have been
a better compromise? I'd certainly think the higher speed would have
increased the probability of a hit, because it would have reduced the
deflection at launch by 1/3 or so. Also, it would have given the target 1/3
less time to maneuver to avoid the torpedo.

A second question addresses launch speed. Early in the war, drop speed and
altitude were in the 110 knot, 150' range. Later, a couple of plywood
fairings were added to increase drag, lift, and stability, and these add-ons
improved the drop parameters for the torpedo. The sources I've found have
contradictions about the launch envelope after these fairings were added.
Can someone point me to a reputable source for this information?

Thanks,

KB