The game really prizes quality over quantity. I got "Amazing" on lvl5 once I realized that I should just go for the two closest resources, upgrade the hell out of the collectors, and upgrade the hell out of the defenders (but only when shields are completely gone). Efficiency!
It would be an awesome additional challenge if the type of ammo used against a target made a difference, instead of the shots simply being progressively better. Had to mix them up within a siege instead of just using the best one you have all the time. Other than that, definite improvement upon the genre.
When the pole is on the branch, splash the rock and put the visitor on the pole, and then launch it.
When in the pipes, get on the second one, and press the yellow valve.
For the woman, it's all about timing. Now go kill some humans.
 "I Am An Insane Rogue AI"){kind=icon}
 "Flagstaff: Chapter One"){kind=icon}
 "Rizk"){kind=icon}
 "Rebuild"){kind=icon}
 "Sieger"){kind=icon}
 "Viricide"){kind=icon}
 "The Visitor"){kind=icon}
 "Starfighter: Disputed Galaxy"){kind=icon}