Okay, one more thing i realized. You didn't make the scoring too difficult, you made the spawning inconsistent. One run I didn't die and could only get like 8k because only one enemy spawned at a time, but in an other run i made like 18k with 1 death, because most of the times 3 enemy spawned. So don't worry, the game isn't too hard, you just need to get a good run.