I disagree. Sure players will get into the La5, the Yak9u, spit8, 190a5 and the P47m but those planes don't come any where close to the level of the Spit16, Yak3, 190D or the La7. Most planes as shown from Lusches stats show that the majority of regular fighters fit into a giant furball on the chart (ironic), which means these planes are most closely related in performance metrically speaking. This means the fights will be more balanced by reducing the usage of the higher kills planes.
ah, see that is where the domino effect starts. With those planes out of common rotation, new planes will fill that void as the Apex predator of the free plane category. This will, albiet not at first, create the same dilemma that you originally referred to. They may all fit in to the "furball" range of the data posted but the more players use the 5 aircraft that you mentioned, the better they get the more you will see a change to that data and you will find that the new apex predators will separate themselves from the flock and this topic
Please perk or reduce the <insert aircraft design series>
will come again, and again, and again. It's very cyclic.