theres no holy grail...

[Chivas]

I don't see a problem with payed aircraft addons effecting on-line play other than the aircraft not being available to fly on the particular server you like to frequent. The server admins select the aircraft available to the player that best supports the game they are trying to achieve. It may or may not be a bit biased but its their server and their game. If it doesn't suit your needs, join another, or create another server.