It seems to me the EZ mode plane guys, as you put it, are the one's willing to stay and fight. Have fun with the runners and ack huggers once they're gone.
The real question is do we want you here? You always talk big; sign up for the dueling bracket. Put up or shut up.
I've noticed quite the opposite. The EZ mode guys cut and run the second they notice they've lost the advantage.
On the other hand, the guys in the 109's, early Spits, and P-47's are much more willing to stick around. Weather because they know they can't use speed to run, feel they can gain an edge as the fight develops, or are just more ballsy than the Spixteen scut I don't know. But the fights are almost invariably better against the higher ENY planes.
Anyway, if someone is unwilling to leave their P-51D, and would rather log than fly something else, their value is limited only to their subscription cost. And that value is mitigated by constraining the tools HTC can use to adjust game play.
The only thing worse than having them as customers is losing them all at once. But I don't think the number that would quit is great enough that we shouldn't add significantly harsher ENY limits.
As to the country thing, I think HTC should rename them country 1, 2, and 3, and randomize the starting country of every player at the beginning of each tour. You can switch to join with your squadies, but since there is no familiar name to switch to by default, and it breaks up the groups of the little tardlets, it might help alleviate the country loyalty.
And if a mega squad is too big to coordinate with the randomization, well it's probably big enough to be detrimental to game play.