I believe the biggest thing the LW needed was not armor, it was a more modern fighter in 1943-45. The 109 started and ended the war as a front line fighter. While it was still good in 1945, it should have been supplemented/replaced much sooner. Think about that, the allies added the Tempest, P-38, P-47,P-51, Yak-9, LA-7, just to name some. All the while the LW added the 190D and Me-262. Yes they had updated versions of the 109, but those could not compare to more modern designs.