Mammoths...
Scrin: Carriers - If you dont have some, as soon as there are Mammoths on the field your strategy is bad.
Nod: Beam Cannons - They have bigger range and should be used in the offense.
GDI: Mammoths and Zone Troopers - Zone Troopers are like Mammoths, just with double firepower and less health, so keep an eye for snipers. They also detect stealthed units, so the EMP wont help . GDI owns everything if you are fast enough.
I hope that helped... But every battle needs its own strategy, this could work sometimes, but isnt the 100% win strategy.
I wish I could upload some replays, I fought some evil rushers with these tactics as GDI on 2vs2. My ally retreated into my base after the first wave (which cost me 1 Powerplant + 1 Refinery) and then harvested my Tiberium. So I had less money in that match. But finally I owned/pawned them alone.
One of them even called me a Jackhammer