* Get the game on F-Droid * More enemy variety * A way of increasing difficulty without it suddenly becoming impossible * Mothership art * A story mode? * The main menu stars could do something silly and fun, like change colors, maybe taking the menu colors with them. * Purchasable Mothership upgrades (like turrets), and make all upgrades exponentially more expensive for higher tiers * Sounds effects for upgrades * etc., etc.