-Smaller squads
-more likely to be wiped
-fuel & popcap concentrated on less units, means losing them is a bigger setback than losing one as allies.
Hence, what you say is not true.
Balance in even match ups (by rank) in 3vs3+ depends mostly on the map.
If you have less flanking options : Axis favored
Big, wide open maps: Allies favored
Says the guy who's player card indicates his greatest success are as axis random in large games....
Popcap is absolutely a disadvantage for USF particularly at low-mid level skill. Late game is dominated by vehicles and a small number of robust vehicles are easier to micro and keep alive than a large number of paper vehicles. And "late game" comes quite quickly in large game formats.
As to squad wiping... It takes a real moron to loose vet5 squads. Not that it doesn't happen, and more so now with the vet5 nerf, but they are still super robust. And the MG buffs in large games will shut low skilled allies down hard. To set it up so that someone needs 2 months to L2P and has to find mates to do it is a FLAWED game design unless the intent is a small but more elite player base. I don't think it is.
Randoms should NOT be matched up with AT. Not ever and player waits be damned. To allow it sacrifices the long-term goals (more new players) with short-term gratification (players shouldn't have to wait so long).