Longest 15 minutes of my life, but I did nail it first try! All 1000. This is obviously a pretty for-teh-lulz game so opportunities for improvement seem a bit moot, but why not:
1) Mini-bosses?
2) 950-1000 was a lot more difficult because I couldn't fire diagonally anymore. Squares were too big and clipped into me immediately at that size.
3) Auto-fire, please. My wrist begs you.
4) Use a web-crawler to pull those profile pics. Made me sad seeing that it apparently took ye a lot of manual work to rip and save them each -- if you remake this for an even higher sub count, learn to make one or ask one of us and we could help you pull them all instantly instead.
Overall, nice little time sink. Controls felt nice. Good core. Sweet concept. GG.