Like the game whose sequal is a blockbuster
This game is good. Really good, and it needs only a bit more to be absoloutely PERFECT.
1: Uncap Drone upgrades.
2: Uncap Drone deployment numbers, or else raise the cap very significantly. Offset this with increasing costs per extra done.
The reason for 1 and 2 is that the usefulness of Drones follows a bell curve. They're all but useless when you first deploy them, then you get more and chuck on a few upgrades and they become very useful to you. Then you have 3 of all of them and they're all upgraded to level 8, and you can almost not fire and let them do the killing. Then the enemies get faster, stronger, and more numerous, and suddenly you're back to firing. Then you get back to frantically firing, because the drones can't keep up.
3: Mouse-over tooltips on the buttons would be very, very helpful.
4: Hotkey pausing. Maybe it'll make the game a BIIIT easier - maybe it should be so.
5: Easy mode is still too hard after the enemies ramp up. Fix this.
6: Maybe seperate upgrades for drones, to enhance them in their damage and rate of fire? My drones just can't keep up after awhile.
7: An option to "Lock" drones would be good. Too many times I've tried to shoot something and grabbed a drone instead.