Thank you so much for the feedback!
For the ghost randomisation, I'm afraid that having ghosts spawn at random intervals will seriously mess with the flow of the game. If a ghost is even a second off target, they'll start missing shots which will turn into more threats to the player as bullets fly around, and would just be unfair. Likewise, with the random weapons for each ghost, if a player dies to a randomised weapon, the ghost the next round might not die from it, resulting in a ghost that will just die for no reason.
However, I think a good way to combat this would be to give the player random stats and random weapons at the beginning of each round, with the weapon being constant with their ghost throughout the rest of that game. That way we still have different enemy types as well as different gameplay without messing with the syncing of the ghosts.
And with the whole "exploit-proof" comment, you really tried to exploit the game, didn't you? xD