I want the prologue to be added back because it was fun point farming the zombies into oblivion and running away from the deers. It was funny watching the kleiners get dreamwrecked by them when you're back pedaling to get to the rock. I remember when most of the deers stop coming, there is a rogue deer that comes at the end and it always killed someone who wasn't aware. Good Times.
The weapon upgrader was a thing but I don't think it's coming back (I don't know). I like the mystery box idea but I don't know it should be unlocked until after wave 3, because wave 1-3 zombies are weak against humans already. Also, I think tier 6 weapons could be implemented into the mystery box, but it is a very low chance of getting them like .00134% or a very low number. I think the higher the tier the lower the chance of getting weapons from the specific tier.
Tier 1 weapon: 40% chance
Tier 2 weapon: 30% chance
Tier 3 weapon: 15% chance
Tier 4 weapon: 10% chance
Tier 5 weapon: 4.95% chance
Tier 6 weapon: 0.050% chance