I think this new mode is fun for an arcade mode and would like to see it get better. I feel the Molotov throws need to be less frequent or if the accuracy can be reduce. Also the speed at which the AI moves. While i do feel its a challenge taking an enemy down health wise, it is possible lol. But the fact is AI can sneak up on you so quick in regular co-op mode, that in frenzy it's almost impossible to cover yourself or others. Maybe the speed can be reduced or put at regular speeds and a couple more bots per wave can spawn.
Also the shotgun reloading glitch which has too many reloading animations and sometimes is empty but still says 1 shell.