I'd actually say it's quite a bit different from Geometry Wars. All it really share is genre : Multi-directional Shooter/Twinstick Shooter (at least from my understanding of Geometry Wars). It's a good idea to take a game you know and put a twist on it, and things usually change during development. My original game idea included enemies but I decided to go without it because the game was hard enough as is. I liked your game a lot. You should add some juice after the jam to make it really fun!