Guys let me mention balance and play numbers from Dota that's the n1 game in terms of comp prizes and literal millions of dollars hang on every balance change.
When a hero is underplayed
They make it intentionally OP and buff it
So more people play that hero
When they do and player numbers start to balance or play it too much, they give slight nerfs.
I think you shouldn't be afraid to make a vastly underplayed faction OP and rules lopsided to attract players to it and make them used with playing it. And nerf factions that are over played.
E.g. This event give higher rewards to seps +legion
Make it 15 mill vs 2 for lawful
To reflect the difficulty. You see the kill numbers - why not dynamically adjust the prizes based on kill ratios?
Buff the IDs to have access to more technology
Make the legion ID locked ships even stronger like fixing secondaries range on arbiter, boosting stats etc.
You shouldn't be afraid of this
Will get a lot of flak "forcing people into playing what you want" but fuck it - it will make the game op on paper, but balanced and more fun for everyone in reality