Thanks for your feedback, I Guess I just have to dust off my old files again XD
You don't have to ;). I like to give feedback for fun even on old projects that aren't going to be worked on anymore.
I only noticed now that you can set the speed and spawn time in the settings. But as long as the enemies come one by one it's still rather easy.
If you do continue to work on it you could look into two bugs I noticed:
1. It seems like once you fail to type a word you can't type other words that start with the same letter.
2. Your score doesn't reset when you restart the game.