L4D(2) 2nd Collab Suggestion Request

Hello, everyone!
I'd like to raise this topic to give some potential ideas for L4D Collab that may be profitable for developers and interesting for players.The name of this topic speaks for itself - to suggest BHVR the negotiation with Valve to make the second collab with Left 4 Dead franchise. No matter if it is free like the first DLC or it is required to be paid for.I know that a collaboration is created through close communication with the publisher of the product (in this case it is L4D -> Valve), so I can just suggest some interesting ideas and make Q&A to predict some questions and hope that this post would be noticed by developers.

As for Survivors

I have 2 suggestions:
1. To add legendary skins of all characters (Coach, Rochelle, Ellis, Nick / Zoey, Louis, Francis) for Bill.
2. To make one of L4D2 character (Nick/Ellis/Coach/Rochelle) as survivor character with 3 new perks that fits the survivor best. The rest of characters can be turned into legendary skins for the same survivor. In that case, it is possible to make L4D legendary skins (Zoey, Louis, Francis) for Bill.

As for Killer: One of the Special Infected with 3 new Perks

It can be The Witch, who entered the fog and already got disturbed by survivors.
Terror radius: 32 meters
Movement Speed: 4.6 m/s (115%)
She can be a progressive killer who is becoming more wicked with each generator completed:
Active ability "Growling Rage": The Witch is getting enraged, her eyes are becoming red from fury. Duration: 40 seconds.The Witch makes her signature scream that warns survivors across the whole map everytime she's enraged. Her Terror Radius increases up to 40 meters. Her Basic attack can instantly down a survivor. After putting a survivor into dying state her ability fades away with some fatigue.
As the trial goes, the Witch becomes stronger with her passive abilities:
5 generators left - Blinding or Stunning the Witch by any means (Exception: Decisive Strike/Will to Live) makes her next basic attack to apply a Deep Wound;
4 generators left - Growling Rage allows to down additional survivor (total 2);
3 generators left - Deep Wounded Survivors and Obsession are marked by Killer Instinct during Growling Rage;
2 generators left - Basic attacks are applying Deep Wound;
1 generator left - Refreshes the ability (if it was active) or resets its cooldown (if it is not available to be used);
Powered/Opened Exit Gates - Allows her ability to down all 4 survivor.

The Witch's addons

Iridescent Bloody Dogtag - Putting a Survivor into dying state don't trigger Basic Attack Cooldown. Only active when Exit Gates are powered or opened.

Iridescent Wedding Dress - Growling Rage becomes active when gates are powered. It lasts until the end of the trial.

Cracked Flashlight - Growling Rage activates passively: It activates every time a generator is completed and if the Witch gets blinded or stunned by any means (Exception: Decisive Strike/Will to Live). Duration: 25 seconds. Growling Rage can't be used manually and can't be activated by cooldown shortening.

Bloody Cigarette - Gains 1% haste for each Deep Wounded Survivor.

Pierced Canister - After getting stunned or blinded, next damage generator action will recover 20% of Growling Rage's cooldown.

Rotten Wedding Flowers - Growling Rage gains additional cooldown quickening conditions: Breaking pallet (5%), Damaging generator (10%), Getting Stunned (15%), Getting Blinded (35%).

Broken Pipe Bomb - When entering Growling Rage, the Scream can be heard only by Survivors within your Terror Radius.

Expired Pills - Growling Rage applies Deep Wound instead of putting survivors into dying state. Grants a stackable +100 bonus Bloodpoints for successful hit, up to a maximum of +500.

Some Sugar - Gains 5% haste for 5 second at the beginning and at the end of Growling Rage.

The Witch's Perks

No Mercy - A survivor that blinded you is marked with Killer Instinct while you're blind. While being blind, your Basic Attack can instantly down a survivor.
Green Flu - When you're standing still for 2 seconds you see the aura of survivors within 14 meters. Increases the radius of all Aura-reading abilities by 6 meters.
Blood Harvest - Each time generator is completed, you receive a token up to a maximum of 5 tokens. For each token, you have 3% Haste while not in chase. Blood Harvest is disabled while in chase.

Questions and Answers

Q: Why is this profitable?
A: It may be profitable because Left 4 Dead franchise is one of the best Valve's recognizable masterpiece. I bet that L4D's fanbase would love to be more than Bill or default characters with L4D cosmetics. It can potentially increase online or income from legendary skins and suggested killer.

Q: DBD already has L4D cosmetics that can represent these characters that you're suggesting to add as skins (Meg - Zoey, Jake - Francis, Dwight - Ellis, Claudette - Rochelle).
A: Indeed, but the whole legendary character feels different than default character in cosplay. We have Resident Evil Cosplay by DBD Characters (Felix as Chris Redfield, Feng as Jill) and nowadays we have Jill and that cosmetic option that Feng cosplays and Chris Redfield as Legendary skin for Leon. It is also important to mention that there is no representation for Nick, Louis and Coach.

Q: Why don't you offer some perks for survivors when you offered the killer concept in details?
A: Honestly, I think Killers need more perks to keep up with survivors.

Q: Why Witch?
A: Firstly, she fits the best. Tank is too wide, Smoker would be second Deathslinger, Charger would be another Dash Killer. Boomer would be another Nemesis with Zombies who can Map Control. Hunter and Jokey would be hard to balance. Spitter is another Unknown, just without Teleport. Second, It is possible to play as all special infected in L4D but not as Witch.

Q: Did I recognize references in your Killer suggestions?
A: Actually, you do. They are referring to Left 4 Dead. Killer's addons refers to important (and not so) events of the game.

Q: Do you think your concept is balanced?
A: I don't know. I just offered the concept that may make the Witch gameplay interesting. Everything I suggested can be turned down or changed.

Q: Why do you spend time on that
A: I just hope that this idea would somehow someday be reached to developers. I like this game and I like the way it goes. In addition, I bet there are also people who wants the same thing as I do.