Not procuring more Mossies.....
The biggest blunder I think was not to MASS produce the Mosquito as a bomber.
In terms of materials it cost much less than an 4-engined bomber, it carried only a crew of two and could carry a 4,000 lb bomb load (the same as a B17) all the way to Berlin.
Its survival depended on its ability to fly higher and much faster than the other allied bombers were able to and it could have operated by day or night. Any losses would have been much more sustainable as (not that this is to diminish the sacrifice made by the crews of the "big" bombers) as "only" two crew would be potentially lost with each aircraft.
Imagine what a force of 1,000 Mossies would represent. Better still, being faster in the long nights of winter they (with a new crew) could even have done two sorties per night. How's that for force multiplication?
Just my 2c - but I even suspect that they would have been a popular choice for the aircrew faced with the alternative of a Wimpy, Manchester, Stirling, Halifax or Lanc.
MB