Try decreasing vision, but having an upgrade to increase it again.
Also buying weapons, and adding a few more.
Finally, a new game mode after (insert final weapon here) is unlocked, and you do 3 runs without dying with that said weapon, and its just a mode where you get the best weapon, and its a run and gun.
You control your character, but auto fire is on, and you still get to upgrade.
i love the game (i beat the game now im restarting because i lost my real profile on Kongregate D:) But a speed button like other people say is a great idea.