Depends on the match up. Most matches mass 4 hp soldiers. Throw a sniper in there. Maybe a special unit depending on your class.
Vs scally, try to pressure early and hope you can get away with it. if you allow them too much time they will mass bombshells then things get bad.
If you are scally, get some soldiers until you feel it’s safe to get a bombshell, then keep massing bombshells and push up with them for the win.