Terran don't seem to work well on air at all. Wraiths rarely destroy an enemy, because they are simply too weak. Detectors should always be made early in the game against a terran, either turrets or photon cannons, and if your enemy doesn't do this they're making a huge mistake. It is good to take advantage of this. Battlecruiser Yamato gun should be used against photon cannons, missile turrets, and spore colonies. Science vessels to irradiate templars, defilers, and other nasty units… otherwise EMP shockwave them, if they are in groups. Constantly hitting the enemy with these energy type attacks will eventually bring them down, as long as you are expanding and keeping them from doing so.