I agree that the card system isn't really a problem, I mean if you put time and effort into something, you should be rewarded. Personally the overall problem I see isn't really much of people being to OP or point whores, but rather people just not leading the group. Same thing with the blood arsenal, though most zombies just keep going for tearing through the cade for barricade points, no one really tries to lead them to new tactics to breaking through the cade. For example set in 2 different views:
Humans: Though we point whore yes, the part of point whoring is still beneficial as it can provide easy access to more repairers, as repairing is honestly one of the best ways to profit 100% of the times, take KOR for example. He repairs almost all the time when it's a shit map. Also another problem I didn't address earlier which should also be sought out is the fact that no one ever really cades, so I assume thats the reasoning for people point whoring. Also to get on the fact of the revolver one shotting zombie, that is only if the zombies are going in a straight line, honestly, 108 damage to the head is a lot, yes, but if the zombie is smart and goes in a zig-zag formation, the hitbox is quite hard to hit for most players to get that "one-shot" effect.
Zombies: For the blood arsenal, though it makes people hoarding for barricade points as well as the fact that the zombies basically go for the attack cade 24/7 with no tactics, lets be honest. Once again re-checking the fact that no one tries to lead zombies and when they do, usually its a half-ass job, for example: Everyone go nightmare and attack the cade! (Imagery of cade: The prop is seperated to top and bottom, not just one prop blocking the whole entrance like a door cade) To the point, when you say "attack the cade" it's too vague which doesn't help the situation rather than saying: "Every go nightmare and attack the top props!", thats more specific and helps in the definition of tactics. The whole point I'm trying to get for zombies is that no one tries to lead, should people lead can we see tactics be use. (Hint hint: Someone go shade while every one else goes: Nightmare, Ticklemare, etc...)