What is the reason that we see balance focus on a two tier priority level (1v1 followed by other modes). I have played lots of RTS games over several decades and never seen an approach to balance like that.
I am genuinely curious why this game is treated different? Before anyone says it, asymmetry is not a good excuse. Think games like Generals which are even more asymmetrical than this one.
I'll hazard an explanation.
This is actually a game between Allies and Axis. There are five factions, but it is always Allies versus Axis. This was less of an issue at launch, when there were only two factions. But after WFA and then with Brits, the variety of teams has compounded the issue.
What this means is that outside 1v1s, everything is a team match. There is no FFA. You effectively have multiple varieties of two teams that are fundamentally different depending on combination. UKF strategic options in a 1v1 is entirely different than UKF with SU and USF. A team of two ostheer is entirely different than a team of OKW and Ostheer, and both play entirely different from ostheer in a 1v1.
(This is why winrates are absolutely meaningless outside of 1v1s as well. A 4v4 features up to 2 axis factions covering 4 player slots versus up to 3 allied factions covering 4 player slots. You can't discern the performance from a single faction in that environment.)
Also, unlike many RTS, maps almost entirely govern gameplay. I'm painting a very broad stroke, but things like resources tied to map control, sight/shot blockers necessitating unit positioning, directional cover, front/rear armor on vehicles, all have huge impacts on how units and factions interact. Map balance is such a crucial component of the CoH franchise. Though it is often overlooked and even ignored, the way maps play probably are more important than how factions are designed in teamgames. If anything it's a foundational component to faction design.
Also, it is not asymmetry for the sake of asymmetry, it's asymmetric balance. You know: a ton of bricks weighs the same as a ton of feathers. The problem with faction asymmetry is that the factions aren't exactly homologous, and especially since Brits, almost from different games.