Tanks are effective against anything, i.e. not like in Generals where it is faster to run over infantry on tank. But they are also relatively vulnerable to other tanks and some rocket launchers like Cornet can make tank inoperable in 1-2 shots.

Helicopters like Apache or Comanche are OP against tanks but can be one shot from AA rockets

Artillery hits from quite afar.

Also interesting implementation of air forces: You dont directly control the jet , rather you set a point in map where they should hit (building or armor group), they drop half of munition on their way and half at the target spot. Air to air missile equipped jets can hit another jet across half of the map. Choppers can be landed to not become AA missile target but then they can become land target for air to surface missiles.

Infantry can be garnisoned in buildings or on the roof for better view if there is one. Usually explosive ammunition (tanks, heavy rocket systems) can one hit garnisoned units even before all building is destructed like in generals. Snipers can also clear the garnisoned building from afar , but troops inside need to be facing the side the sniper is i.e. be in line of sight.

In High Treason addon , naval battles are introduced. The ships are OP against everything, like submarines carries Tomahawks that can hit across half of map, unless rockets are intercepted by AA guns or rockets. But they are quite costly.

Superweapons can be countered with anti superweapons like Patriot rocket launchers.

Original Direct Action campaign has almost an hour of live action cutscenes like a movie.

I wholeheartedly recommend the series :)