Would a bioshok chapter satisfy you?

The only Shock I want is System Shock. Give me Mommy SHODAN, you can keep your Big Daddy. And like AnneBonny said above, if we're getting an underwater map I'd rather SOMA. Frictional Games is surely worthy of inclusion.

Never played Bioshock so have no investment in it either way.

Bioshock would lose so much of what makes it interesting in DBD. Like Big Daddies are iconic, but they aren't actually that interesting. Little Sisters, Big Sister, Splicers, and the named bosses the more interesting characters. Visually speaking, Bioshock has a lot of aesthetic touches that adds to the feel of the game that would absolutely get lost in DBD.

It's just not a good fit.

I'm absolutely in love with the idea of a potential Bioshock chapter and having the Big Daddy as a potential killer, it is by far my most wanted Video Game license right above Outlast. There's so much room to create such an interesting power, between the little sisters that they are attached to and relentlessly protect, a giant oversized drill combined with a massive hulking armored frame, plasmids which provide a unique source for other powers and forms of utility. Bioshock is a wealth of ideas and fits like a Glove into Dead by Daylight's slasher thematic filled with empowered killers that are hosts to a myriad of all sorts of strange abilities.

I think I really fell in love with the idea after seeing the fanmade chapter / character model posted up on Youtube. They did a fantastic job with the somber seaside music, the inhuman whale calls and mechanical sounds that a Big Daddy makes, and even a decent power idea as well.

That's an incredibly subjective point, personally, I became interested in Bioshock purely because of the design of the Big Daddies. I love the exterior visual design inspired by vintage diving suits combined with a steampunk aesthetic, just as much as the interior lore about these genetically enhanced humans whose bodies were grafted into the suits themselves, and their subsequent psychological programming which compels them to be the protective caretakers of the little sisters- acting as their personal guardians.

Not to mention the deeper lore about the different versions of big daddies and the prototype Subject Delta. I find them to be incredibly intriguing and with plenty of depth to satisfy that interest. Compared to your average splicer, named bosses, or even the Big Sisters, I still actually like The Bouncers way more, and you would think it's because of all that intrigue that made them so iconic in the first place. I'd have to disagree with you entirely on nearly every point you made in your comment.

Not only that, but the Bouncer works even better than the other ideas you listed because he's actually been licensed out to another game once before, meaning that the license holders would probably be open to doing so again. The Bouncer was featured in Playstation's Smash Bros. esque title for the PS3, Playstation All-Stars: Battle Royale as a fully playable fighter. Meaning that they would be more likely to license this character out again in the future, seeing as they've already collaborated with other studios in the past.

Bioshock would be a perfect addition to DBD, and the only true difficulty I see with a potential chapter is having too many ideas to fit into a single kit for this character. However, I'd consider this to be a "good problem" to have as it essentially means they get to pick and choose which aspects of the Bouncer are most important to the fantasy of the character, which ones reflect the character and the overall franchise the best, and which provide the most unique additions to DBD and fit in the overall flow that open up brand new avenues for players to explore.

Worst case scenario, we end up with a Nemesis-like situation where the devs end up compromising for the sake of DBD more than they branch out in bold directions. (Although let's be real, we all knew Nemesis wasn't getting a rocket launcher). I honestly don't think this is a bad thing, as overall I think most DBD players welcomed Nemesis as an intimidating killer who brought the core idea of what Nemesis was (an engineered and lethal bioweapon) and brought with him the first AI controlled elements to a killer. Looking back, I think more people would rather keep him than remove him completely if they had they option to, the people that wouldn't are fringe-case purists who don't accept anything less than perfection from their beloved franchises. Which I don't personally believe is a realistic expectation, given some compromises have to be met to translate and adapt nearly any character from other video games into Dead by Daylight at all.