Robert,
wonderful info on the 110 H! I don't spend any time researching German ac anymore so it is great to see these gems popping up.
I'm sure you are quite correct about not wanting to slow production in order to change the canopy. Even in cases where the changes in performance were quite dramatic toward the positive it could take literally years before the change was instituted. The perfect example of that is the single tail for the B-24 which I describe in some detail in my book "Consolidated Mess". Though the tests performed in 1943 on the single tail were overwhelmingly positive in terms of stability, handling, speed, drag, etc., and communications from Europe commands began to come in to DC and Wright Field almost immediately asking when they could expect new single-tail B-24s, it wasn't until the B-24N that the USAAF would have received this mod. The Navy, of course, got single-tail stretch B-24s in the form of the PB4Y-2. The long logistics trail of finding manufacturers to produce all the component parts for a new tail assembly and building up a backlog of parts to enhance manufacturing of the finished aircraft, plus the potential impact on the delivery of parts for the existing design, make it clear why this change didn't take place earlier.
Once again, nice research and drawings, Robert!
AlanG