we should be able to get those variants for every jet in the game if we buy them but also for free if we can complete some objectives like for example:
objective 1: fly jet X for 500hrs
objective 2: destroy 1000 ai enemy jets with jet X
objective 3: destroy 250 enemy Sam sites with jet X
objective 4: complete a game in BVR with 8 kills and 0 death with jet X
objective 5: destroy 500 enemy jets in multiplayer with jet X
this is just an example and btw it could be for more variants not just golden ones.
by doing so having multiple skins of each aircraft will mean that who owns them is a veteran of Jet Attack Move; we could use the word Ace to describe players with all of the skins of every applicable jet (bombers, transport helicopters and so on) are excluded or might have different objectives