How about allowing the tactical missile to hit the air units? Including units are catapult, bluehawk, stingray, and hornet. The tactical missile can target the orbital units, but they can't shoot down the air units. This is quite strange. I think the tactical missile can also provide a good method to counter the air titan Zeus since the weapon range of tactical missile is much longer than the weapon range of Zeus. And I believe the tactical missile launchers won't become overpower even if they can target the air units. They are expensive, and their rate of fire are very slow. Moreover, they don't have area of effect. Thus, they are certainly less efficiency than T2 flank cannon and T1 AA. However, they can shoot down air unit from long distance.