Really awesome! Only oddities/bugs I've noticed are that I unlocked the DMG pickup and when selecting it I was still in the cruiser, and pause mode makes all enemy cars/trees/pickups disappear. Actually fun to play, though! I enjoyed it thoroughly. :)
Oh hmm, I'll double check that DMG Pickup glitch.
So, pulling back the curtain, the reason all the sprites disappear is because they're not actually sprites! Everything except the player and the cop are actually projectiles being shot at you from offscreen!
EDIT: Confirming the pickup glitch should be fixed!