i'd recommend removing the money packet mechanic and instead make it increase the money gained from kills by a %. This would make it more of an end-game thing, right now its, even with the recent nerf, stronger in the long run then upgrading the turret, only because a 75% increase multiplied over and over quickly outpaces anything else. I feel like a 3-5% increase in cash made per kill per level would work pretty well.
 "Auto Turret"){kind=icon}
 "BattleCry"){kind=icon}