I dont really know the other squads yet, but I dont have a problem flying with JG3, or against them, they seem AOK to me. The problem with the 1948 planeset was not JG3 really, more that the Dweebfire IX and the S-199 (109) were on the same side. You cant really blame JG3, who probably have a few hours in the 109, to want to fly that, then add to that the folks who want the Dweebfire IX no matter what side its on and you have lopsided numbers.
With this last planeset side numbers have been much closer. The last night I flew, sunday, JG3 was comming straight for the fight and at low alt so I cant really say there was much to complain about.
I do think there is more cooperation on the allied side between solo guys that are not in squads and those in allied squads than there is on the Axis side, but other than that things dont seem much different to me on either side of the fence.