There needs to be a bigger variety of power-ups from Cargo Trains
Also in my opinion, you should be able to store and use them later with push of a button.
Some examples i thought of:
Immortality - damage and collision immunity for 3(?) seconds, but you can't fire and are slowed
Time stop - all units and projectiles stop moving for 5(?) seconds. You and you projectiles are not affected
Slowdown - same idea as time stop but only slows down units and projectiles instead of completely stopping them.
Portable black hole - you deploy a mine that creates a black hole.
Laser gun - allows you to fire a laserbeam instead of your weapon single time for 6(?) seconds. -90% total thrust and +30(?)% damage reduction while firing