I don't know what you expect from the Scott? To wipe static team weapons in 6 shots? That would make the balance team screech from OPness.
That's why everyone plays Urban Assault, because the Calliope actually DOES do that.
Also, the barrage vs the Autoattack has massively different accuracy characteristics, so the Pack Howi 3 shots most HMGS with barrage. Its just the AA is garbage and as such its blob punishment is irrelevant.
As long as Allied HMGs cannot reasonably suppress a blob before it runs it over, Allies need some kind of blob removal tool non-doc. USF doesn't have one, neither does UKF. That's why most USF team players go Urban Assault, as it gives that tool in the best commander with that tool. I play a LOT of UKF Land Mattress, and it has saved games vs mass blobbed infantry.
I guess the Bulldozer Sherman could have its AI cranked up enough to slaughter blobs, but it would need the survivability to not get quickly murdered in those late game situations. Still, that's a Doctrinal option.
The UKF Mortar could be buffed to the point it wins arty duels OR is very cheap and quick to move, but that would be painful to play against.