Like Chillipino said, would you be able to share some of these videos with us? If you showed some of the videos you've been sent during a livestream, we may be able to mend the disconnect between what you and the dev team are seeing as intended gameplay vs what the players have been calling bugs. As it is now, we both sit on different sides of the table and both see something different. And your livestreams seem to be the perfect place for the players to hear your side and understand your thoughts behind what we call bugs.
For instance, the video below is one I sent in regarding the damage "bug" (I can remove the video from this, and an earlier, post if you deem it necessary). In this video, I record three confrontations with a player who has been effected by the "bug". The third fight in particular (starting at 27 seconds) shows the player's shield breaking at 32 seconds, for the next three seconds, the amount of damage he takes drops 90% (202 crit to 20 crit). With perk stacking, the only possible amount of damage reduction he could have achieved in that instant is 56% (not crouched, not standing still, had not killed anyone) through Cellular Armor and Thick Skin. The only possible way to achieve 90% damage reduction is if he had a
34% damage reduction while reloading weapon mastery (no shield has a damage reduction bonus that would have applied in state that he was in) and was reloading his sawed off, instead of switching to his SMG. Furthermore, after Thick Skin's three seconds of protection has ended, he has 65% damage reduction for 6 more seconds (131 base damage at the beginning of the fight, 46 damage at the end of the fight, back up to normal damage levels at the 43rd second of the video). At least 9 seconds after his shield has broken, he has achieved damage reduction levels that are impossible under normal circumstances, for periods of time that are impossible under normal circumstances.
Sadly, I forgot to inspect him on video, to prove how his loadout would not have given him those damage reduction levels. However, from the fire rate of his smg, it is likely a VOT Pulser (common among all who have this bug) and from the reduced damage he took from the first 3 shots on his shield I assume he was using a strong guardian shield (if so, that may be an indication of a bug, as guardian shields offer protection when the shield is full, after the first shot the shield is no longer full) that offers
34% (87 damage from the first three hits vice 131 from the following hits) damage reduction when shields are full.
I hope I was clear in my explanation, because from this video alone, it is evident that perks are not where the bug lies when it comes to damage reduction. As far as I could tell, all of them worked correctly throughout the three fights. It is the bonuses on the gun and, possibly, the shield that have been causing the all the problems.
http://youtu.be/He75iaaeCGg