This whole Eny debacle is the reason I think that plane popularity should play a higher roll in determining its Eny. The masses will fly the planes that give them the best chances to succeed in the MA environment, which they are actually defining themselves. There's a reason for a plane's popularity/scarcity in the air. For example to show I'm not being biased, I'll say I think it is time for the K4's eny(due to its influx in popularity to go along with its obvious performance advantages) to be lowered to 15 or even 10 maybe.
As for the Ta152 and P47N? Cmon, look at its stats Htc, both planes should be in the 10 Eny range.
You are absolutely right about the 109 K-4 deserving a lower ENY on account of performance, to say nothing of the 152 and N-Jug.
However, popularity has absolutely nothing to do with how much or how little the player gets to work with when he rolls the aircraft, so why make it an issue?
On top of that, it looks like in 2008 the K-4 was not even the most popular German plane...hard to tell all the different shades of that chart apart though.
Certainly the 190 family was used for a lot more kills than the 109 family.
So go on and admit the reason it needs its ENY lowered is because it possesses an extremely beneficial combination of top speed, power loading, and lift loading relative other planes...albeit it also has possession of a few special "quirks".