Since we have a very large spread of players in the campaign game, even within one side, I suggest the following option - to make the option “Play any Campaign”.
The main point: When you click on it, the player who gets into battle will receive 2X experience, he will play for the side he chose (allies / axis), but in a random campaign.
When you click "play for any team in any campaign”, the player can get anywhere at all, but for a 3X increase in experience gained in battle (taking into account booster, prem, etc.).
At the same time, the player must be ready to play this mode, and if the player leaves it often, this mode is blocked for him for an N-th amount of time / fights.
Although this is a dubious solution, it should at least somewhat alleviate the problem of low online in a particular company.
Thanks to @116659358 for the English translation
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