Balancing a nation freedom deck build mod

So while on a caffeine fueled bender this weekend I threw together a freedom deck mod by nation for Warno, so basically

• There are now 13 new deck rules, one for each nation that contains all units and all transports flagged with that nation (so something like Pz.Grenadier is a West Germany only unit despite being available in 11 ACR).
• There are 53 new divisions, one for each vanilla division. The "freedom" version of a division has the same AP slot costs as its parent vanilla division, but with a freedom deck list (so 119y has access to all SOV flagged units, but [1,1,2,3,3] log slot costs, [1,1,2,3,3] inf slots costs, etc).
• Unit availability/vet curves are set whatever division has the most of them (so the US decklist has 6 cards of M1A1 because some us div has 6 cards of M1A1s).
• Luxembourg units are part of the belgian decklist as there are no LUX divs in the game.
• Units not part of any div aren't part of the game (rip T-80UK).

Playtesting this with some friends it was immediately obvious that US/SOV are S tier divs and everyone else is trash tier. Is there something that can be to kinda bring nations in line with each other so that there's some sense of balance? It doesn't need to be "everyone's about the same viability", I'm more hoping for a vanilla-ish tierlist spread vs "21 S-tier US/SOV divs and 32 F-tier everyone else divs".

(Or maybe this shouldn't actually matter and screw balance in a mod like this lol)