things changed very rapidly in the late 1930s and very early 40s.
Going from 87 octane (PN 68.?) fuel to 100/130 allowed for an increase of about 85% in cylinder pressure without detonation, assuming the engine was strong enough to withstand the beating and could handle the extra thermal load.
Flaps went from simple split flaps (air brakes) in 1935/36 to the double slotted Fowler flaps used on the A-26 in 1942.
alloys and structures also advanced.
The US also built thousands of wooden airplanes (not including the gliders) during WW II. Just about all were trainers and the few large planes didn't turn out well (less said about the XP-77 the better).
Beech was building these in 1942.
which was primarily wood.
The Famous Stearman PT-17 used a steel tube fuselage with fabric covering but the wing structure was wood and fabric covered.
Cessna built over 5000 of these
The wing structure was built around laminated spruce spar beams,
truss-style spruce and plywood ribs, and plywood wing leading edges and wing tips.
There were a number of other aircraft and construction methods.
Unless you have access to the reasoning behind the decision/s you may be dealing with a lot of supposition and armchair quarterbacking.
There is a lot of stuff in books and on the internet that just ain't so.
Here is a link to the mission records of the 303rd bomb group. 364 missions from Nov 17th 1942 to April 25th 1945. (planes carried ten 500lb bombs each to Pilsen Czechoslovakia) that show that the B-17 carried more than 4000lbs to Berlin.
303rd BG Combat Missions and Reports