I don't know why you have such a bad opinion about Germans and there are in fact quite a few advantages if you mount the landing gear on the fuselage.
FYI, an Extra 300 has a much higher power to weight ratio than the early 109s and a fuselage mounted landing gear. It doesn't seem to be another crazy, completely stupid German dump idea.
If a 109 actually weighs 50% less than you wrote, yes, then it's IMO completely wrong.
Maybe if the very light weight ground adjustable aluminium trim tabs (your steel plates) and the fuselage would be made of steel it would double the weight of a 109 ;)
Again, there are no 'steel plates' for trimming on an aircraft and it wouldn't make any sense because you couldn't bend them!
The reason for me to be that 'critical' is that you are a real pilot and hence I was surprised about your inaccurate/misleading post.