Some very interesting points made... having different unit stats is probably the best way, but it is so much work.
I don't play 4v4 or 3v3 often. Sometimes when I'm bored and don't want to be as stressed, I play with big teams.
It is less micro; if you lose a gren squad at ten minutes it's not that big of a deal.
I think the biggest issue in 1v1 is call-ins/heavy tanks. A big part of 4v4 imbalance is the same thing.
I think halving the fuel income of all factions would be beneficial to balance. Not sure how OKW would do with that...maybe strategic points should give one less fuel and/or fuel cache bonuses would not apply to okw players? Also, cutting off resources to players should be easier. If two players are cut off from the map, but if the other two players in the other base sector are connected to territory, the two 'cut off' players still receive resources.
These are all my ideas/brainstorming. I'm not saying they would all work, but they could all be altered slightly to improve balance.
There's not much that can be done with automatching...It seems to be working fine on 1v1, so I assume it works fine with 4v4, but, there are eight players instead of two. Your best chance is to play during the hours of the day (or night) when CoH2 has the most players online.
I like playing 4v4/3v3. It's fun, not as stressful, and awesome at times (awesome in the sense of instilling fear... when railway artillery obliterates clumped infantry). It's fun to see so many units on the field and there's always action somewhere to watch or to help your friends out.
It's incredibly rewarding to flank the south of La Gleize with three Shermans, driving west to east, to catch a Jagdtiger in the ass