So, I took a look at the Tropes topic, and decided to choose three of them to base my game on:
1.One Hitpoint Wonder
3.You Require More Vespene Gas
And then I wrote down simple gameplay ideas, and came up with this concept:
Top-down space shooter with a semi-newtonian Asteroids-like control scheme. The player can thrust forward and turn left or right - no backwards thrust! The game takes inertia into consideration, so you won't stop moving automatically, and that counts for both the forward thrust AND the turning - if you want to stop turning, you have to turn to the other side, and if you want to stop going forwards, you have to turn around 180 degrees and thrust. There is, however, a limit to speed (hence semi-newtonian). The objective is to eliminate increasingly difficult waves of enemies and get a high score. The game is endless and randomly-generated. The player ship is destroyed with a single hit, but the player can collect "shield units", adding an extra hit-point, although the player can only have one of those at a time. They are dropped by enemies and destructible asteroid props (that can also kill the player). The player starts with 3 lives, and it's Game Over when all are lost. Thrusting forwards and firing also depletes the ship's ENERGY, and when all of the energy is depleted, the player loses a life. Enemies can drop energy orbs, that recover a little bit of energy.
Well, that's all I have for now! Once I get home, I might actually get something started right away, hopefully.