Teach players what counters what.
For example: Light frigates counter both flak and carriers. Long Range Frigates counter Light frigate. Flak counters Long Range Frigates and Fighters...etc...etc....
That might be the problem with this idea, if you start spouting this sort of thing at first time playes, they'll think "too complicated" and ignore the tutorial.
Some more about static defenses would be nice (give them a chance to use last resort at least once even if they play Advent and Vasari for the rest of their live ).