Hudson
Be assurred that Boeing took under consideration considerable experience with engine fires shared by all manufacturers data banks.
All of your "what ifs" were postulated and obvious "factuals" as well.
It was noted that the greater risk with uncontrolled engine fires was on the ground while the greater risk with crew error under stressfull situations was beyond v1.
You are probably correct in pointing out that some "what if" scenarios are not properly accounted for under the recommended procedure, but the idea was to save more lives in our imperfect world.