Rocking soundtrack! Smooth controls. Moving around and setting everything on fire is just as satisfying as it sounds.
Obstacles that have been fully burned should appear as a pile of ashes, if at all. A bulky object in flames still "reads" to the eye as an obstacle that will block the player.
A few simple sound effects would be nice. You can use bfxr or a similar utility to create some 8-bit-style blips and bloops.
Graphically, the game is pretty bare. It would benefit from some interesting environments.
Lastly, the instant respawn is good in that it doesn't waste the player's time, but it's actually so fast that the first couple of times, I just thought I had been teleported!