green skull rewards

Are the weapon or item prizes worth pushing for? I'm on around 4k skulls and next item is a level 16 pirate pistol at 5200, so looks to be a long road to level 20+ items...

Also I've just been farming level 1 and occasional full run when backpack is full, but couldn't be bothered anymore. If you kill the final rooftop boss then purposely get killed, does it respawn?